Question

find the sum of first 10 multiples of 8​

Answer 1

Step-by-step explanation:

The first ten multiples of 8 are 8, 16, 24, 32, 40, 48, 56, 64, 72, and 80

the sum of first 10 multiples of 80 is 440

Answer 2

Given,

First 10 multiples of 8.

To find,

The sum of the first 10 multiples of 8.

Solution,

We can easily solve this problem by following the given steps.

According to the question:

We have:

First 10 multiples of 8.

8,16,24,---

Now, this series is an AP because the difference between the two consecutive terms is the same.

The first term (a) = 8

Common difference(d) = second term - first term

d = 16-8

d = 8

We know that the following formula is used to find the sum of n terms of an AP:

Sn = n/2 [2a+(n-1)d]

S10 = 10/2 [2(8)+(10-1)8]

S10 = 5 [16+(9)8]

S10 = 5 (16+72)

S10 = 5(88)

S10 = 440

Hence, the sum of the first 10 multiples of 8 is 440.