Question

9 girls and 1 boy go for a party .every girl spends Rs 40 and the boy pays Rs 720 more than the total average.what is the expenditure of the boy​

Answer 1

Let Avg exp of all 10 be =x

Then

9x40 + (x + 720) = 10x


9x = 1080

X= 120

Total expense = 120 x 10 =1200

Boys exp = 1200 - 360 =840

Answer 2

The expenditure of the boy​ is 840

Step-by-step explanation:

Let the average be x

We are given that 9 girls and 1 boy go for a party .

Total people = 9+1=10

Each girl pays = Rs.40

9 girls pays =$40 \times 9 = 360$

The boy pays Rs 720 more than the total average.

So, Cost for boy = 720+x

$Average = \frac{\text{Total cost}}{\text{Total people}}$

$x=\frac{360+720+x}{10}\\10x=360+720+x\\9x=1080\\x=\frac{1080}{9}\\x=120$

Cost for boy = 720+x=720+120=840

Hence  the expenditure of the boy​ is 840

#Learn more:

In a school, 720 are boys and 40% are girls. Find the number of girls.

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