Question

Find the average of first 20 multiples of 50

Answer 1

we have to find the average of first 20 multiples of 50.

first 20 multiples of 50 ⇒1 × 50, 2 × 50, 3 × 50, 4 × 50 , 5 × 50 ........ 20 × 50

⇒50, 100, 150, 200, 250 ......... 1000

now find the sum of first 20 multiples of 50.

using formula, Sn = n/2[first term + last term]

here n = 20, first term = 50 and last term = 1000

so, Sn = 20/2[50 + 1000]

= 10[1050]

= 10500

now average = sum of observations/number of observations

= Sn/n

= 10500/20

= 1050/2

= 525

therefore, average of first 20 multiples of 50 is 525.

Answer 2

$\huge\mathcal{Answer:}$

First 20 multiple of 50

$1 \times 50 \: \: 2 \times 50 \: \: 3 \times 50 \: \: 4 \times 50 \: \: 5 \times 50 ..20 \times 50$

$50 \: \: 100 \: \: 150 \: \: 200..1000$

$sn = \frac{n}{2} (first \: term + last \: term)$

$sn = \frac{n}{2} (50 + 1000)$

$= 10(250)$

$= 10500$

$average = \frac{sum \: of \: observation}{no \: of \: observation}$

$= \frac{sn}{n}$

$= \frac{10500}{20}$

$= \frac{1050}{2}$

$= 525$