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3 years ago

8

Each boy in a class has 7 pockets and each girl in that class has 11 pockets. How many boys and how many girls are there in this

class if there are 147 pockets and 17 heads?

2 answers:

jeyben [28]3 years ago

8 0

Answer: There are 10 boys and 7 girls in the class.

Step-by-step explanation:

Let x be the number of boys and y be the number of girls then according to the question we have the following equations :-

$x+y=17...............................(1)\\\\7x+11y=147...........................(2)$

The value of y from (1) will be

$y=17-x$ , substitute this in equation (2), we get

$7x+11(17-x)=147\\\\\Rightarrow\ 7x+187x-11x=147\\\\\Rightarrow\ 187-4x=147\\\\\Rightarrow\ -4x=147-187\\\\\Rightarrow\ -4x=-40\\\\\Rightarrow\ x=10$

∴ $y=17-10=7$

Hence, there are 10 boys and 7 girls in the class.

Aloiza [94]3 years ago

6 0

10 boys equals 70 pockets
7 girls equals 77 pockets

that equals 147 pockets and 17 heads

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