From a class 24 boys, a boy aged 10 years leaves the class and in his

1.	From a class 24 boys, a boy aged 10 years leaves the class and in his place a new boy is admitted. As a result the average age of the class is increased by 2 months. What is the age of the new boys ?
Answer» Let the average age of the class be x years. Then the total age of the class = 24x years New average age of the class = \((x-\frac{2}{12})\) years = \((x-\frac{1}{6})\) years Let the age of the new boy be y years. Given, \(\frac{24x-10+y}{24}=x-\frac16\) ⇒ 24x-10+y = 24x - 4 ⇒ y = 6 ∴ The age of the new boy is 6 years

From a class 24 boys, a boy aged 10 years leaves the class and in his place a new boy is admitted. As a result the average age of the class is increased by 2 months. What is the age of the new boys ?

Answer»

Let the average age of the class be x years.

Then the total age of the class = 24x years

New average age of the class = \((x-\frac{2}{12})\) years = \((x-\frac{1}{6})\) years

Let the age of the new boy be y years.

Given, \(\frac{24x-10+y}{24}=x-\frac16\)

⇒ 24x-10+y = 24x - 4 ⇒ y = 6

∴ The age of the new boy is 6 years

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From a class 24 boys, a boy aged 10 years leaves the class and in his place a new boy is admitted. As a result the average age of the class is increased by 2 months. What is the age of the new boys ?

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