Operis Interview Questions, Process, and Tips

877.4

2.01

In 30 mins- Thief – 20km, Owner – 0km
In 1hr – Thief – 40km, Owner – 25km
In 1.5hrs – Thief – 60km, Owner – 50km
In 2hrs – Thief – 80km, Owner – 75km
In 2.5hrs – Thief – 100km, Owner – 100km

Answer: In 2.5 hours the owner would have overtaken the Theif

I have seen a few say 25% as an answer to this. But looks
like their math isn’t good and is extremeley complex to
have an asnwer of 25% to this question. Consider – Rs.1.00/-
per mango; so 40 mangoes = Rs.40.00/-, implies Rs.4.00/-
extra at the end of the deal. So he’s left with Rs.44.00/-
after selling 40 mangoes implies a profit of Rs.4.00/- over
Rs.40.00 = 44/40 = 110% which means his profit is 10%.
Hope this helps…
Thanks.

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.

By 1hour both trains meet, so the distance travel by fly in
1hr is 120km.

trick
(r/10)*(r/10)
(20/10)*(20/10)
4% decrese

Chi-ca-go

Robin =72
Dravid = 98
Azhar = 22
Sachine = 98
Total score = 290