Find the sum of the first 15 multiples of 8. | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The multiples of $8$ are $8, 16, 24, 32, \ldots$These numbers form an Arithmetic Progression $(A.P.)$ where the first term $a = 8$ and the common

Vedclass · Accepted Answer

$960$

Vedclass · Answer

(B) The multiples of $8$ are $8, 16, 24, 32, \ldots$These numbers form an Arithmetic Progression $(A.P.)$ where the first term $a = 8$ and the common difference $d = 8$.We need to find the sum of the first $n = 15$ terms.The formula for the sum of the first $n$ terms of an $A.P.$ is $S_n = \frac{n}{2}[2a + (n - 1)d]$.Substituting the values: $S_{15} = \frac{15}{2}[2(8) + (15 - 1)8]$.$S_{15} = \frac{15}{2}[16 + 14(8)]$.$S_{15} = \frac{15}{2}[16 + 112]$.$S_{15} = \frac{15}{2}(128)$.$S_{15} = 15 	imes 64 = 960$.

Find the sum of the first $15$ multiples of $8.$

Similar Questions

In the following arithmetic progression $(AP)$,find the missing terms in the boxes: $\square, 13, \square, 3$.

$1^{2}, 5^{2}, 7^{2}, 73, \ldots$ are $APs$? If they form an $AP,$ find the common difference $d$ and write three more terms.

Find the $20^{th}$ term from the last term of the $AP : 3, 8, 13, \ldots, 253.$

$A$ small terrace at a football ground comprises of $15$ steps each of which is $50 \, m$ long and built of solid concrete. Each step has a rise of $\frac{1}{4} \, m$ and a tread of $\frac{1}{2} \, m$. Calculate the total volume of concrete required to build the terrace (in $m^3$).

In an $AP$ given $a=5, d=3, a_{n}=50,$ find $n$ and $S_{n}$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module