Question

the no. of boys and girls in a classare in the ratio of 9:7 .the no. of boys is 12 more than the no. of girls. what is the total strength​

Answer 1

Given :-

• No.of boys and girls, ratio = 9 : 7
• Number of boys = 12 more than number of girls.

To find :-

• Total strength of class

Solution :-

Let the no. of boys & girls be 9n & 7n respectively.

According to question :

⇒ 9n = 7n + 12

⇒ 9n - 7n = 12

⇒ 2n = 12

⇒ n = 12/2

⇒ n = 6

Now finding number of boys & girls :

⇒ No. of boys = 9n

⇒ No. of boys = 9(6)

⇒ No. of boys = 54

⇒ No. of girls = 7n

⇒ No. of girls = 7(6)

⇒ No. of girls = 42

Now finding total strength :

⇒ Total strength = No. of boys + No.of girls

⇒ Total strength = 54 + 42

⇒ Total strength = 96

Therefore,

Total strength of class = 96 .

Answer 2

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$\huge\tt{GIVEN:}$

• Boys and girls ratio in a class = 9:7
• 12 Boys are more than girls

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$\huge\tt{TO~FIND:}$

• Total strength

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$\huge\tt{SOLUTION:}$

Let the number of boys and girls be 9x & 7x

According the the question,

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↪9x = 7x+12

↪9x-7x = 12

↪2x = 12

↪x = 12/2

↪x = 6

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Now, numbers of boys would be 9x = 9×6 = 54

Now, numbers of girls would be 7x= 7×6 = 42

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