A man covers frac{1}{3} of his journey by train at 80, km / h , next frac{1}{3} by 60, km / h and re

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4.Average

medium

A man covers $\frac{1}{3}$ of his journey by train at $80\, km / h ,$ next $\frac{1}{3}$ by $60\, km / h$ and the rest by bicycle at $30 \,km / h$. Find the average speed of the man during the whole journey. (in $km/h$)

$65$

$45$

$48$

$53 \frac{1}{3}$

Solution

Average speed of the man for the whole journey $=\frac{3 \times 80 \times 60 \times 30}{80 \times 60+60 \times 30+30 \times 80}$

$=\frac{3 \times 80 \times 6 \times 3}{8 \times 6+6 \times 3+3 \times 8}=\frac{3 \times 80 \times 3}{8+3+4}=\frac{9 \times 80}{15}=3 \times 16=48\, km / h$

Standard 13

Quantitative Aptitude

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hard

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medium

A man covers $\frac{1}{3}$ of his journey by train at $80\, km / h ,$ next $\frac{1}{3}$ by $60\, km / h$ and the rest by bicycle at $30 \,km / h$. Find the average speed of the man during the whole journey. (in $km/h$)

Solution

Similar Questions

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