Races and games
- In 1 km race, P beats Q by 72 m in 12 s. Find the P's time over the course.
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According to the formula,
Time taken by the winner/Distance covered by the loser = Difference of winning time/ Difference of winning distance
⇒ Time taken by P//(1000 - 72) = 12/72Correct Option: C
According to the formula,
Time taken by the winner/Distance covered by the loser = Difference of winning time/ Difference of winning distance
⇒ Time taken by P//(1000 - 72) = 12/72
∴ Time taken by P = (12/72) x 928
= 464/3 = 1542/3 s
- In a 250 m race, the ratio of speeds of A and B is 1 : 2, If A has a start of 140 m, then A wins by how many metres ?
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To reach the winning post, A has to cover (250 - 140)m = 110 m
From the the ratio of 1 : 2 ,
When A covers 1m, then B covers 2 mCorrect Option: D
To reach the winning post, A has to cover (250 - 140)m = 110 m
From the the ratio of 1 : 2 ,
When A covers 1m, then B covers 2 m.
When A covers 110 m, then B covers
( 2 x 110)m = 220 m
∴ A wins by (250 - 220) = 30 m
- A runs 1% times as fast as B. If A gives B a start of 30 m, how far must the winning post be, so that A and B reach it at the same time ?
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A is 13/4 faster than B.
Then, ratio of the rates of A and B = 7 : 4
3 m are gained in a race of 7 m .
30 m are gained in a race of (7/3) x 30 = 70 mCorrect Option: D
A is 13/4 faster than B.
Then, ratio of the rates of A and B = 7 : 4
3 m are gained in a race of 7 m .
30 m are gained in a race of (7/3) x 30 = 70 m
