In a race of senior citizens, Mr. A can g… | Answer

Subject

Quantitative Aptitude

Topic

Speed & Distance

In a race of senior citizens, Mr. A can give his fiend Mr. B a start of 20 m and Mr. C a start of 39 m in a race of 100 m. How much start can Mr. B give Mr. C?
Reading

ক)

20 m

খ)

24.75 m

গ)

20.25 m

ঘ)

23.75 m

ঙ)

40 m

Explanation

Speed = distance/time Let the speed of Mr. A, Mr. B, and Mr. C are a, b and c respectively. Given that, Mr. A can give his friend Mr. B a start of 20 m and Mr. C a start of 39 m in a race of 100 m. Since Mr. A can give his friend Mr. B a start of 20 m Time taken by them must be equal.

\Rightarrow \frac{{100}}{a} = \frac{{80}}{b}

and

\frac{{100}}{a} = \frac{{61}}{c}

then ,

\frac{a}{b} = \frac{{100}}{{80}}\;and\frac{a}{c} = \frac{{100}}{{61}}

\Rightarrow \frac{c}{b} = \frac{{61}}{{80}} \times \frac{{100}}{{100}}

\Rightarrow \frac{c}{b} = \frac{{61}}{{80}}

Multiply both denomination and numerator by 1.25

\Rightarrow \frac{c}{b} = \frac{{61}}{{80}} \times \frac{{1.25}}{{1.25}}

\Rightarrow \frac{c}{b} = \frac{{76.25}}{{100}}

\Rightarrow \frac{{100}}{b} = \frac{{76.25}}{c}

Thus, Mr. B covers 100m in the same time Mr. C covers 76.25 m. Thus, Mr. B can give Mr. C ahead start of (100 – 76.25) m = 23.75 m

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In a race of senior citizens, Mr. A can give his fiend Mr. B a start of 20 m and Mr. C a start of 39 m in a race of 100 m. How much start can Mr. B give Mr. C?Reading

In a race of senior citizens, Mr. A can give his fiend Mr. B a start of 20 m and Mr. C a start of 39 m in a race of 100 m. How much start can Mr. B give Mr. C?

Explanation

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In a race of senior citizens, Mr. A can give his fiend Mr. B a start of 20 m and Mr. C a start of 39 m in a race of 100 m. How much start can Mr. B give Mr. C?
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