Out of nine persons , 8 persons spent Rs., 30 each for their meals. ninth one spent Rs., 20 more tha

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Out of nine persons$, 8$ persons spent $Rs.\, 30$ each for their meals. The ninth one spent $Rs.\, 20$ more than the average expenditure of all the nine. The total money spent by all of them was (in $Rs.\,$)

A

$260$

B

$290$

C

$292.50$

D

$400.50$

Solution

Expenditure of $9^{th}$ person $=$ $Rs.\,x$

Now, according to the question,

$x-\frac{x+8 \times 30}{9}=20$

$\Rightarrow \frac{9 x-x-240}{9}=20$

$\Rightarrow \quad 8 x-240=180$

$\Rightarrow \quad 8 x=240+180=420$

$\Rightarrow x=\frac{420}{8}=52.5$

Total expenditure $=Rs.\,(52.5+240)=Rs.\, 292.5$

Standard 13

Quantitative Aptitude

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