Quant Question Of The Day: 30
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Arithmetic
Rahul covers a circular track in 15 minutes while Gandhi does it in 10 minutes. Both start running in the same direction but from diametrically opposite position and Rahul is ahead of Gandhi initially. If they run for 3 hrs and 20 min then how many times Gandhi would have crossed Rahul?
1. 5
2. 6
3. 7
4. 8
5. None of these .
In 30 minutes Gandhi can cover the circular track 3 times while Rahul can cover only 2 times. This means in 30 min Gandhi can cover 1 round more than Rahul.
Initially Rahul was half round ahead of Gandhi and Gandhi would have taken 15 min to cover that.
Gandhi crossed Rahul first time after 15 min, second time after 45 min , third time after 75 min and so on.
Hence In 200 min(i.e. 3 hrs and 20 min) Gandhi would have crossed Rahul 7 times.
Option 3.
Gandhi would cross Rahul for the first time after 15 min. and then he will cross him after every 30 min. Therefore in 3hrs 20min he will cross Rahul 7 times.
c
7 times
Option 3
L.C.M of 15 and 30 is 30
Then 200/30 is 6.67 = 7 approx
3 is the correct option.
Congratulations Everyone!