Question

the mean weight of 15 boys is 43 kg. if 2 boys with weights 34 and 35 kg join them find the new mean weight.

Answer 1

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✝️ Required Answer:

✏GiveN

• Mean weight of 15 boys = 43 kg.
• Two boys with 34 and 35 kgs were added.

✏To FinD

• Find the new mean weight.....?

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✝️ How to solve?

We need to find the mean, and mean is calculated by:

$\large{ \boxed{ \rm{Mean = \frac{Total \: sum \: of \: all \: items}{No. \: of \: all \: items} }}}$

Here, mean is the mean weight, total sum of all items means sum of weights of all boys, and no. of all items means no. of boys.

✏ So, Let's solve this question by using the above formula.

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✝️ Solution:

⏺ Given,

• Mean weight of boys = 43 kg
• No. of boys = 15

By using formula,

$\large{ \rm{ \rightarrow \: 43 = \dfrac{</p><p>Sum \: of \: all \: weights}{15} }} \\ \\ \large{ \rm{ \rightarrow \: Sum \: of \: all \: weights = 15 \times 43}} \\ \\ \large{ \rm{ \rightarrow \: Sum \: of \: all \: weights = \boxed{ \rm{645}}}}$

⏺ Now,

• Two boys are added
• Weights = 34 kg and 35 kg.

✒Total weight now,

= 645 + 34 + 35 = 714 kg

No. of boys now = 17

By using formula,

$\large{ \rm{ \rightarrow \: Mean \: weight = \frac{714}{17} }} \\ \\ \large{ \rm{ \rightarrow \: Mean \: weight = \boxed{ \red{42}}}}$

Hence, the New mean weight of boys = 42

$\large{ \therefore{ \underline{ \underline{ \purple{ \rm{Hence \: solved \: \dag}}}}}}$

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Answer 2

Answer:

The answer is in this copy. I hope it will help you