Question

find the sum of first five multiples of 3?

Answer 1

A=D=3
S5=5/2(2A+4D)
S5=5(A+2D)
S5=5(3+6)
S5=5(9)
S5 = 45

Answer 2

Answer:

45

Step-by-step explanation:

First five multiples of 3 are :

$3 \times 1 =3$

$3 \times 2=6$

$3 \times 3=9$

$3 \times 4=12$

$3 \times 5=15$

So, the first five multiples of 3 are 3,6,9,12,15

Now the sum of first five multiples of 3  = 3+6+9+12+15 = 45

Hence the sum of first five multiples of 3 is 45