Question

A boy walks from his house to his school. If he walka at a speed 2½ km per hour, he reaches his school in 30 minutes.How far is the school from his house?





ans with explanation​

Answer 1

$\underline{\red{Given:}}</h3><h3>$

• A boy walks at a speed 2½ km per hour (2.5 km/ph).
• He reach at his school in 30 minutes.

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$\underline{\red{To \: find:}}$

• How far is the school from his house.

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$\underline{\red{Solution:}}$

Let the distance between boy’s house and school be ‘x’,

Hence, 2½ km = 2.5 km and 1 hour = 60 minutes.

∴The distance between the boy's house and school is,

$\frac{2.5 \: km}{60 \: min} = \frac{x}{30 \: min} \\ \\ = > \frac{2.5}{60} = \frac{x}{30} \\ \\ = > (2.5 \times 30) = (60 \times x) \\ \\ = > 75 = 60x \\ \\ = > x = \frac{ \cancel{(75}) ^{5} }{ \cancel{(60})^{4} } \\ \\ = > x = \frac{5}{4} \\ \\ = > \green{ \boxed{ x = 1.25 \: km}}$

∴ The distance between boys house and school is 1.25 kilometres.