MECON Aptitude Questions

                                                   Mecon Sample Placement Paper

General Aptitude

1. If Rs. 10 be allowed as true discount on a bill of Rs. 110 due at the end of a certain time, then the discount allowed on the same sum due at the end of double the time is:
A. Rs. 20 
B. Rs. 21.81
C. Rs. 22 
D. Rs. 18.33

Answer: D. Rs. 18.33

Explanation:
S.I. on Rs. (110 – 10) for a certain time = Rs. 10.
S.I. on Rs. 100 for double the time = Rs. 20.
T.D. on Rs. 120 = Rs. (120 – 100) = Rs. 20.
T.D. on Rs. 110 = Rs. ( 20/120 x 110) = Rs. 18.33

2. The true discount on a bill due 9 months hence at 16% per annum is Rs. 189. The amount of the bill is:
A. Rs. 1386 
B. Rs. 1764
C. Rs. 1575 
D. Rs. 2268

Answer: B. Rs. 1764

Explanation:
Let P.W. be Rs. x.
Then, S.I. on Rs. x at 16% for 9 months = Rs. 189.
x x 16 x 9/12 x 1/100 = 189 or x = 1575.
P.W. = Rs. 1575.
Sum due = P.W. + T.D. = Rs. (1575 + 189) = Rs. 1764.

3. Rs. 20 is the true discount on Rs. 260 due after a certain time. What will be the true discount on the same sum due after half of the former time, the rate of interest being the same?
A. Rs. 10 
B. Rs. 10.40
C. Rs. 15.20 
D. Rs. 13

Answer: B. Rs. 10.40

Explanation:
S.I. on Rs. (260 – 20) for a given time = Rs. 20.
S.I. on Rs. 240 for half the time = Rs. 10.
T.D. on Rs. 250 = Rs. 10.
T.D. on Rs. 260 = Rs. ( 10/250 x 260) = Rs. 10.40

4. A and B can together finish a work in 30 days. They worked at it for 20 days and then B left. The remaining work was done by A alone in 20 more days. A alone can finish the work in?
A. 48 days 
B. 54 days
C. 50 days 
D. 60 days

Answer: D. 60 days

Explanation:
Work done by A and B in 20 days = (1/30 * 20) = 2/3
Remaining work= ( 1 -2/3) = 1/3 Now,1/3 work is done by A in 20days
Whole work will be done by A in (20×3) = 60 days.

5. A can do a certain job in 25 days which B alone can do in 20 days. A started the work and was joined by B after 10 days. The number of days taken in completing the work was
A. 12 and half days 
B. 15 days
C. 14 and 2/9 days 
D. 16 and 2/3 days

Answer: D. 16 and 2/3 days

Explanation:
Work done by A in l0 days = (1/25) *10 = 2/5.
Remaining work = 1 – (2/5) = 3/5
(A+B)’s 1 days work = (1/25) + (1/20) = 9/100
9/100 work is done by them in 1 day.
hence 3/5 work will be done by them in (100/9) * (3/5) = 20/3days.
Total time taken = (10 + 20/3) = 16 * (2/3) days.

6. If 10 men or 18 boys can do a piece of work in 15 days, then 25 men and 15 boys together will do twice the work in?
A. 4 and half days 
B. 8 days
C. 9 days 
D. 36 days

Answer: C. 9 days

Explanation:
10 men = 18boy hence 1 man = 18/10 boys
25 men + 15 boys = (25 * 18/10) + 15 = 60
now more work more days
more boys less days1 * 60 * x = 2*18*15 or x = (2*18*15)/60 = 9 days

7. A certain number of men complete a piece of work in 60 days. If there were 8 men more, the work could be finished in 10 days less. How many men were originally there?
A. 30 
B. 36
C. 32 
D. 40

Answer: D. 40

Explanation:
Originally 1et there be x men.
More men, less days
(x + 8): x ∷ 60:50
So, x + 8 / x = 60/50 or x = 40.
Hence, there were 40 men, originally.

8. Ram can do a piece of work in 8 days which Shyam can finish in 12 days. If they work at it on alternate days with Ram beginning, in how many days, the work will be finished?
A. 9 and 1/3 
B. 9 and 1/24
C. 9 and 1/2 
D. 10 and 1/3

Answer: C. 9 and 1/2

Explanation:
(Ram + Shyam)’s 2 days work = (1/8) + (1/12) = 5/24
Their 8 days work = (5/24) * 4 = 5/6
Their 8 days work = (5/6) + (1/8) = 23/24
Remaining work = (1 – (23/24))
Now it is Shyam’S turn.
1/12 work is done by him in 1 day.
1/24 work is done by him in (12 * (1/24)) = 1/2 day.
Total time taken = 9 and half days.

9. Amy has to visit towns B and C in any order. The roads connecting these towns with her home are shown on the diagram. How many different routes can she take starting from A and returning to A, going through both B and C (but not more than once through each) and not travelling any road twice on the same trip?
A. 10 
B. 8
C. 6 
D. 4

Answer: B. 8

Explanation:
Amy can travel clockwise or anticlockwise on the diagram.
Clockwise, she has no choice of route from A to B, a choice of one out of two routes from B to C, and a choice of one out of two routes from C back to A. This gives four possible routes.
Similarly, anticlockwise she has four different routes.
Total routes = 8

10. A man walking at the rate of 5 km/hr crosses a bridge in 15 minutes. The length of the bridge (in metres) is
A. 600 
B. 750
C. 1000 
D. 1250

Answer: D. 1250

Explanation:
speed = (5×5/18)m/sec
= 25/18 m/sec.
Distance covered in 15 minutes = (25/18 x 15 x 60)m
= 1250 m.

11. The distance between two cities A and B is 330 Km. A train starts from A at 8 a.m. and travel towards B at 60 km/hr. Another train starts from B at 9 a.m and travels towards A at 75 Km/hr. At what time do they meet?
A. 10 a.m 
B. 10.30 a.m
C. 11 a.m 
D. 11.30 a.m

Answer: C. 11 a.m

Explanation:
Suppose they meet x hrs after 8 a.m
then,
[Distance moved by first in x hrs] + [Distance moved by second in (x-1) hrs] = 330.
Therefore, 60x + 75(x-1) = 330.
=> x=3.
So,they meet at (8+3) i.e, 11a.m.

12. The speed of a car increases by 2 kms after every one hour. If the distance travelling in the first one hour was 35 kms. what was the total distance travelled in 12 hours?
A. 456 kms 
B. 482 kms
C. 552 kms 
D. 556 kms

Answer: C. 552 kms

Explanation:
Total distance travelled in 12 hours =(35+37+39+…..upto 12 terms)
This is an A.P with first term, a=35, number of terms,
n= 12,d=2.
Required distance = 12/2[2 x 35+{12-1) x 2]
=6(70+23)
= 552 kms.

13. A train covers a distance in 50 minutes, if it runs at a speed of 48kmph on an average. Find the speed at which the train must run to reduce the time of journey to 40 minutes.
A. 50 km/hr 
B. 60 km/hr
C. 65 km/hr 
D. 70 km/hr

Answer: B. 60 km/hr

Explanation:
We are having time and speed given, so first we will calculate the distance. Then we can get new speed for given time and distance.
Lets solve it.
Time = 50/60 hr = 5/6 hr
Speed = 48 mph
Distance = S*T = 48 * 5/6 = 40 km
New time will be 40 minutes so,
Time = 40/60 hr = 2/3 hr
Now we know,
Speed = Distance/Time
New speed = 40*3/2 kmph = 60kmph

14. The least perfect square, which is divisible by each of 21, 36 and 66 is:
A. 213444 
B. 214344
C. 214434 
D. 231444

Answer: A. 213444

Explanation:
L.C.M. of 21, 36, 66 = 2772.
Now, 2772 = 2 x 2 x 3 x 3 x 7 x 11
To make it a perfect square, it must be multiplied by 7 x 11.
So, required number = 2∧2 x 3∧2 x 7∧2 x 11∧2 = 213444

15. A group of students decided to collect as many paise from each member of group as is the number of members. If the total collection amounts to Rs. 59.29, the number of the member is the group is:
A. 57 
B. 67
C. 77 
D. 87

Answer: C. 77

Explanation:
Money collected = (59.29 x 100) paise = 5929 paise.
Number of members = √5929 = 77.

16. How many two-digit numbers satisfy this property.: The last digit (unit’s digit) of the square of the two-digit number is 8 ?
A. 1 
B. 2
C. 3 
D. None of these

Answer: D. None of these

Explanation:
A number ending in 8 can never be a perfect square.

17. The square root of 64009 is:
A. 253 
B. 347
C. 363 
D. 803

Answer: A. 253

Explanation:
√64009=253

18. (17)3.5 x (17)? = 178
A. 2.29 
B. 2.75
C. 4.25 
D. 4.5

Answer: D. 4.5

Explanation:
Let (17)3.5 x (17)x = 178.
Then, (17)3.5 + x = 178.
3.5 + x = 8
x = (8 – 3.5)
x = 4.5

19. If 5a = 3125, then the value of 5(a – 3) is:
A. 25 
B. 125
C. 625 
D. 1625

Answer: A. 25

Explanation:
5a = 3125  5a = 55=> a = 5.
5(a – 3) = 5(5 – 3) = 52 = 25.

20. (256)0.16 x (256)0.09 =?
A. 4 
B. 16
C. 64 
D. 256.25

Answer: A. 4

Explanation:
(256)0.16 x (256)0.09 = (256)(0.16 + 0.09)
= (256)0.25
= (256)(25/100)
= (256)(1/4)
= (44)(1/4)
= 44(1/4)
= 41
= 4

21. If m and n are whole numbers such that m n = 121, the value of (m – 1) n + 1 is:
A. 1 
B. 10
C. 121 
D. 1000

Answer: D. 1000

Explanation:
We know that 112 = 121.
Putting m = 11 and n = 2, we get:
(m – 1) n + 1 = (11 – 1) (2 + 1) = 103 = 1000.

22. If 3(x – y) = 27 and 3(x + y) = 243, then x is equal to:
A. 0 
B. 2
C. 4 
D. 6

Answer: C. 4

Explanation:
3x – y = 27 = 33 x – y = 3 ….(i)
3x + y = 243 = 35 x + y = 5 ….(ii)
On solving (i) and (ii),we get x = 4.

23. Rajender invests a part of Rs. 12000 in 12% stocks at Rs. 120 and the remainder in 15% stock at Rs. 125. If his total dividend per annum is Rs. 1360, how much does he invest in 12% stock at Rs. 120?
A. Rs. 4500 
B. Rs. 6000
C. Rs. 5500 
D. Rs 4000

Answer: D. Rs 4000

Explanation:
Let investment in 12% stock is Rs. x.
Investment in 15% stock Rs. (12000 – x).
(12/120) * x + 15/125(12000-x) = 1360
5x + 72000 -6x hence x = 4000

24. A man invested Rs. 1552 in a stock at 97 to obtain an income of Rs. 128. The dividend from the stock is?
A. 8% 
B. 9.7%
C. 7.5% 
D. None of these

Answer: A. 8%

Explanation:
By investing Rs. 1552, income = Rs. 128.
By investing Rs. 97, income = Rs. (128/1552) * 97= Rs.
Dividend = 8%.

25. By investing Rs. 1620 in 8% stock, Sandeep earns Rs. 135. The stock is then quoted at?
A. Rs. 106 
B. Rs. 80
C. Rs. 96 
D. Rs. 108

Answer: C. Rs. 96

Explanation:
To earn Rs. 135, investment = Rs. 1620.
To earn Rs. 8, investment = Rs. (1620/135) * 8= Rs.96.
Market value of Rs. 100 stock = Rs. 96.

26. In order to obtain an income of Rs. 650 from 10% stock at Rs. 96, one must make an investment of?
A. Rs. 6500 
B. Rs. 3100
C. Rs. 9600 
D. Rs. 6240

Answer: D. Rs. 6240

Explanation:
To get Rs. 10, investment = Rs. 96
To get Rs. 650, investment = Rs. (96/10) x 650 = Rs. 6240.

27. Rs. 9800 is invested partly in 9% stock at 75 and 10% stock at 80 to have equal amount of incomes. The investment in 9% stock is?
A. Rs. 4800 B. Rs. 5400
C. Rs. 5000 D. Rs. 5600

Answer: C. Rs. 5000

Explanation:
Let the investment in 9% stock is x.
investment in 10% stock = (9800 – x)
9/75 * x = 10/80(9800 – x) hence x = 5000

28. The simple interest on a certain sum of money at the rate of 5% p.a. for 8 years is Rs. 840. At what rate of interest the same amount of interest can be received on the same sum after 5 years ?
A. 6% 
B. 9%
C. 8% 
D. 10%

Answer: C. 8%

Explanation:
Sum = 100*840 / 5*8 = 2100
rate required = 100*840 / 2100 * 5 = 8

29. A sum of money at simple interest amounts to Rs. 2240 in 2 years and to Rs. 2600 in 5 years. What is the principal amount?
A. Rs. 1520 
B. Rs. 2000
C. Rs. 1880 
D. None

Answer: B. Rs. 2000

Explanation:
SI for 3 year = 2600-2240 = 360
SI for 2 year 360/3 * 2 = 240
principal = 2240 – 240 = 2000

30. Avinash borrowed Rs. 5000 from Sanjay at simple interest. After 3 years, Sanjay got Rs. 300 more than what he had given to Avinash. What was the rate of interest per annum?
A. 2% 
B. 8%
C. 5% 
D. 10%

Answer: A. 2%

Explanation:
(100 * 300 )/(5000*3) = 2%

31. Rs. 800 amounts to Rs. 920 in 3 years at simple interest. If the interest rate is increased by 3%, it would amount to how much ?
A. Rs. 992 
B. Rs. 1112
C. Rs. 1056 
D. Rs. 1182

Answer: A. Rs. 992

Explanation:
Principal = 800 SI = 120 Time = 3 year
Rate = (100*120/800*3) = 5%
New rate = 8 % principal = 800 time 3 year
SI = (800*8*3/100) = 192
New amount = 800 + 192

32. If A lends Rs. 3500 to B at 10% p.a. and B lends the same sum to C at 11.5% p.a., then the gain of B (in Rs.) in a period of 3 years is?
A. 107.50 
B. 157.50
C. 115.50 
D. 177.50

Answer: B. 157.50

Explanation:
Gain = (3500*11.5*3 /100) – (3500*10*3/100) = 157.50

Answer: B. 157.50

33. There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is?
A. 20 
B. 80
C. 100 
D. 200

Answer: C. 100

Explanation:
Let the number of students in rooms A and B be x and y respectively.
Then, x – 10 = y + 10 x – y = 20 ——————–1
and x + 20 = 2(y – 20) x – 2y = -60 ——————–2
Solving 1 and 2
x = 100 , y = 80.
The required answer A = 100.

34. One-third of Rahul’s savings in National Savings Certificate is equal to one-half of his savings in Public Provident Fund. If he has Rs. 1,50,000 as total savings, how much has he saved in Public Provident Fund ?
A. Rs. 30,000 
B. Rs. 50,000
C. Rs. 60,000 
D. Rs. 90,000

Answer: C. Rs. 60,000

Explanation:
Let savings in N.S.C and P.P.F. be Rs. x and Rs. (150000 – x) respectively. Then,
1/3x=1/2(150000-x)
(x/3)+(x/2)=75000
5x/6=75000
X=(75000×6)/5=90000
Savings in Public Provident Fund = Rs. (150000 – 90000) = Rs. 60000

35.To fill a tank, 25 buckets of water is required. How many buckets of water will be required to fill the same tank if the capacity of the bucket is reduced to two-fifth of its present ?
A. 10 
B. 35
C. 62.5 
D. Cannot be determined

Answer: C. 62.5

Explanation:
Let the capacity of 1 bucket = x.
Then, the capacity of tank = 25x.
Let the capacity of 1 bucket = x.
Then, the capacity of tank = 25x.
New Capacity of bucket=2/5x
Required number of bucket= (25x)/(2x/5)
(25x) (5/2x)
=125/2 =62.5

36. A man has Rs. 480 in the denominations of one-rupee notes, five-rupee notes and ten-rupee notes. The number of notes of each denomination is equal. What is the total number of notes that he has?
A. 45 
B. 60
C. 75 
D. 90

Answer: D. 90 

Explanation:
Let number of notes of each denomination be x.
Then x + 5x + 10x = 480
16x = 480
x = 30.
Total number of notes = 3x = 90.

37. The price of 10 chairs is equal to that of 4 tables. The price of 15 chairs and 2 tables together is Rs. 4000. The total price of 12 chairs and 3 tables is?
A. Rs. 3500 
B. Rs. 3750
C. Rs. 3840 
D. Rs. 3900

Answer: D Rs. 3900

Explanation:
Let the cost of a chair and that of a table be Rs. x and Rs. y respectively.
Then, 10x = 4y or y = 5 /2x.
15x + 2y = 4000
15x + 2 x 5/2 x = 4000
20x = 4000
x = 200.
So, Y= (5/2) (200)= 5000
Hence, the cost of 12 chairs and 3 tables = 12x + 3y
= Rs. (2400 + 1500)
= Rs. 3900.

38. What number should be added to each of the numbers 8, 21, 13 and 31 so that the resulting numbers, in this order form a proportion?
A. 2 
B. 5
C. 3 
D. 7

Answer: B. 5

Explanation:
(8+x)/ (21+x) = (13+x)/ (31+x)
Then, (8 + x) (31 + x) = (13 + x) (21 + x)
Or 39x + 248 = 34x + 273 or 5x=25 or x = 5.

39. A certain amount was divided between Salim and Rahim in the ratio of 4: 3. If Rahim’s share was Rs. 2400, the total amount was?
A. Rs. 5600 
B. Rs. 9600
C. Rs. 3200 
D. Rs. 16800

Answer: A. Rs. 5600

Explanation:
Let S = 4x and R = 3x. Total amount = 7x.
Then, 3x = 2400 so x= 800.
Total amount = 7x = Rs. 5600

40. An amount of money is to be distributed among F, Q and R in the ratio 3: 5 : 7. If Qs share is Rs. 1500, what is the difference between Ps and Rs shares?
A. Rs. 1200 
B. Rs. 1600
C. Rs. 1500 
D. Rs. 1900

Answer: A. Rs. 1200

Explanation:
Let P = 3x, Q = 5x and R = 7x.
Then, 5x = 1500 ⇒ x = 300. P=900, Q=1500 and R = 21OO.
Hence, (R – p) = (2100 – 900) = 1200