Question

The average of 20 numbers is 15 and that of the first five is 12.Accordingly, what is the average of the remaining numbers?

Answer 1

$\huge\mathfrak\blue{Answer:}$

Given:

• We have been given that the average of 20 numbers is 15
• Average of first 5 numbers is 12

To Find:

• We have to find the average of remaining numbers

Solution:

Since we know that

$\boxed{\sf{\pink{Average = \dfrac{Sum \: of \: Terms}{Number \: of \: Terms}}}}$

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$\bigstar \: \: \underline{\large\mathfrak\orange{According \: to \: First \: Condition:}}$

$\hookrightarrow \sf{Average \: of \: 20 \: numbers = 15}$

$\hookrightarrow \sf{ \dfrac{Sum \: of \: 20 \: numbers}{20}=15}$

Cross Multiplying the terms:

$\hookrightarrow \sf{Sum \: of \: 20 \: numbers = 15 \times 20 }$

$\hookrightarrow \sf{Sum \: of \: 20 \: numbers = 300}$

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$\bigstar \: \:\underline{\large\mathfrak\orange{According \: to \: second \: Condition:}}$

$\hookrightarrow \sf{Average \: of \: first \: 5 \: numbers = 12}$

$\hookrightarrow \sf{ \dfrac{Sum \: of \: first \: 5 \: numbers}{5}=12}$

Cross Multiplying the terms:

$\hookrightarrow \sf{Sum \: of \: first \: 5 \: numbers = 12 \times 5 }$

$\hookrightarrow \sf{Sum \: of \: first \: 5 \: numbers = 60}$

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$\bigstar \: \: \underline{\large\mathfrak\green{Average \: of \: remaining \: number:}}$

$\implies \sf{Sum \: of \: remaining \: number }$

$\implies \sf{Sum \: of \: 20 \: numbers - Sum \: of \: first \: 5 \: numbers }$

$\implies \sf{300 - 60}$

$\implies \sf{240}$

Average of Remaining numbers is:

$\hookrightarrow\sf{Average = \dfrac{Sum \: of \: 20 \: number}{20-5}}$

$\hookrightarrow \sf{Average = \dfrac{240}{15} }$

$\hookrightarrow \sf{Average = \cancel{\dfrac{240}{15}} }$

$\hookrightarrow \sf{Average = 16 }$

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$\boxed{\sf{\large\mathfrak\red{Average \: of \: remaining \: numbers = 16}}}$

Answer 2

Answer:

hy dude refer to above pic

Step-by-step explanation:

plz mark brainliest ✌

have a good day❣