Question

It costs Rs. $6000	ext{/-}$ and Rs. $6100	ext{/-}$ respectively to paint the $4$ walls of $2$ square halls, of the same height. If the length of one hall exceeds the length of the other by $1	ext{ m}$ and the cost of painting is Rs. $5	ext{ per sq.m.}$, what is the height of the two walls?

Accepted Answer

D. Area of 4 walls of square hall $= 4 	imes a 	imes h$. Cost of painting $= 4 a h 	imes 5 = 20 ah$. Given $20 ah = 6000 \implies ah = 300$. For second hall: $20 (a + 1) h = 6100 \implies (a + 1) h = 305$. Subtracting: $h(a + 1) - ah = 305 - 300 \implies h = 5	ext{ m}$.

Height of square hall walls

Explanation

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