St john's college, cambridge Interview Questions, Process, and Tips

1/24-1/40
(5-3)/120
2/120
1/60
60 minutes

3 min

1

yea may be they are brothers only by father or by mother

Which means the train will travel 180 m in 6 seconds so
We need to convert this into minutes
6×10 = 60s= 1 minute.
180×10 = 1800 m train will travel 1.8 km in 1 minute.
1.8×60 = 108 kmph

30%

around 29.8

The last person covered 120.71 meters.
It is given that the platoon and the last person moved with
uniform speed. Also, they both moved for the identical
amount of time. Hence, the ratio of the distance they
covered – while person moving forward and backword – are
equal.
Let’s assume that when the last person reached the first
person, the platoon moved X meters forward.
Thus, while moving forward the last person moved (50+X)
meters whereas the platoon moved X meters.
Similarly, while moving back the last person moved [50-(50-
X)] X meters whereas the platoon moved (50-X) meters.
Now, as the ratios are equal,
(50+X)/X = X/(50-X)
(50+X)*(50-X) = X*X
Solving, X=35.355 meters
Thus, total distance covered by the last person
= (50+X) + X
= 2*X + 50
= 2*(35.355) + 50
= 120.71 meters
Note that at first glance, one might think that the total
distance covered by the last person is 100 meters, as he
ran the total lenght of the platoon (50 meters) twice.
TRUE, but that’s the relative distance covered by the last
person i.e. assuming that the platoon is stationary.

Joe is fencing in a square area of 576 square feet.
Fence posts, which are needed every three feet, cost 32.00 each.
The fencing cost 4.50 per foot. What is the total cost of the fencing materials?

Solution:-
Area of Square is 576 sq ft.
so, the length of side = root(576) = 24 ft

Since the fencing would be done on the perimeter, we would need that
formula is 4*side = 96 ft.

Number of Fence post needed = 96/3 = 32

1 Fence post cost = 32
32 Fence Post cost = 32 * 32 = 1024

Fencing cost = Perimeter * fencing cost = 96 * 4.5 = 432

Total Cost = 432 + 1024 = 1456

Money will give Luxury but not experience

C

#1: N = 1, f(N) = 1
#2: N = 199981, f(N) = 199981
#3: N = 199982, f(N) = 199982
#4: N = 199983, f(N) = 199983
#5: N = 199984, f(N) = 199984
#6: N = 199985, f(N) = 199985
#7: N = 199986, f(N) = 199986
#8: N = 199987, f(N) = 199987
#9: N = 199988, f(N) = 199988
#10: N = 199989, f(N) = 199989
#11: N = 199990, f(N) = 199990
#12: N = 200000, f(N) = 200000
#13: N = 200001, f(N) = 200001
#14: N = 1599981, f(N) = 1599981
#15: N = 1599982, f(N) = 1599982