Question

The average age of 600 scholars of a school is 10.75 years by the enrollment of the 40 new scholars the average is reduced to 10.4375 years. find the average age of the new scholars


Option :
$a) \: 3 \frac{4}{5}$
$b) \: 5\frac{3}{4}$
$c) \: 4\frac{3}{5}$
$d) \: 6\frac{3}{4}$


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Answer 1

(d) is your answer brainlist

Answer 2

Answer:

$5\frac{3}{4}$

Step-by-step explanation:

Given :The average age of 600 scholars of a school is 10.75 years by the enrollment of the 40 new scholars the average is reduced to 10.4375 years.

To Find :Find the average age of the new scholars

Solution:

The average age of 600 scholars of a school is 10.75 years

$Average = \frac{\text{Sum of ages of 600 scholars}}{\text{No.of scholars}}$

$10.75 = \frac{\text{Sum of ages of 600 scholars}}{600}$

$10.75 \times 600=\text{Sum of ages of 600 scholars}$

$6450=\text{Sum of ages of 600 scholars}$

By the enrollment of the 40 new scholars the average is reduced to 10.4375 years.

$10.4375  = \frac{\text{Sum of ages of 640 scholars}}{640}$

$10.4375 \times 640  =\text{Sum of ages of 640 scholars}$

$6680 =\text{Sum of ages of 640 scholars}$

Sum of ages of new 40 scholars = Sum of 640 scholars ages - Sum of 600 scholars ages

Sum of ages of new 40 scholars =6680-6450=230

$\text{Average age new scholars} = \frac{230}{40}$

                                                             = $\frac{23}{4}$

                                                             = $5\frac{3}{4}$

So, Option B is true .

Hence  the average age of the new scholars is  $5\frac{3}{4}$