In a race of 600 metres, A can beat B by 60 metres and in a race of 500 metres, B can beat C by 50 metres. By how many metres will A beat C in a race of 400 metres?
76 metres
80 metres
70 metres
84 metres
Answer: Option A
A runs B runs C runs
600 metres race 600m 540 m
500 metres race 500 m 450m
Combing ratio A runs B runs C runs
300metres - 2700meters - 2430metres
Unitary A runs B runs C runs
Method 400mtres - 360 metres - 324 metres
∴ A beats C by 400-324 = 76 metres.
26 km
32 km
30 km
28 km
Answer: Option B
Total Time = 7hrs
Let the distance travelled by foot @ 8kmph be x kms
∴ distance travlled by bicycle @ 16kmph be (80-x)kms
ATQ. 7hr = x/8 + (80-x)/16
∴ 7 = (2x + 80 - x)/16
∴ x = 32kms
If 20 men can build a wall 112 metres long in 6 days, what length of a similar wall can be built by 25 men in 3 days?
65mtr.
52mtr.
70mtr.
78mtr.
Answer: Option C
20 men is 6 days can build 112 metres
25 men in 3 days can build = 112*(25/20)x(3/6)
= 70 meters
If the compound interest on a certain sum of money for 3 years at 10% per annum be Rs. 993, what would be the simple interest?
Rs. 880
Rs. 890
Rs. 895
Rs. 900
Answer: Option D
Let P = Principal
A - Amount
We have a = P(1 + R/100)3 and CI = A - P
ATQ 993 = P(1 + R/100)3 - P
∴ P = Rs 3000/-
Now SI @ 10% on Rs 3000/- for 3 yrs = (3000 x 10 x 3)/100
= Rs 900/-
What annual installment will discharge a debt of Rs. 4600 due in 4 years at 10% simple interest?
1000
1030
1100
None of these
Answer: Option A
Let the annual instalment be Rs. 100. The first instalment will be paid one year from now i.e. 3 years before it is actually due. The second instalment will be paid two years from now i.e. 2 years before it is actually due.
The third instalment will be paid 1 year before it is actually due.
The fourth instalment will be paid on the day the amount is actually due.
On the first instalment the interest will be paid for 3 years, on the second for 2 years, on the third for 1 year, on the fourth for 0 year. In total an interest for 6 years will be paid (3 + 2 + 1 + 0) on Rs. 100 @ 10%. Interest = (100 × 6 × 10)/100 = Rs. 60 and the principal is Rs 100 × 4 = Rs 400. The total loan that can be discharged is Rs. 400 + 60 = Rs. 460. Here the technique of Chain Rule will be applied. I.e. for Rs. 460 the instalment required is Rs. 100, for Rs. 4600 the instalment required is 4600 × 100/460 = Rs. 1000.
A number whose fifth part increased by 5 is equal to its fourth part diminished by 5, is