Question

i count on in equal steps my first number is -2, my fifth number is 26 what is my third number?

Answer 1

Answer:

The third number is 12.

Step-by-step explanation:

This is an A.P

so a = -2

and a_5 = 26

now using formula,

a_5 = a + (n-1)d

26 = -2 + (5-1)d

26 = -2 + 4 d

26 + 2 = 4 d

28 = 4 d

d = 28/4 = 7

the third number will be:

a_3 = a + (n-1)d

      = -2 + (3-1)7

      = -2 + 2.7

      = -2 + 14 = 12

Therefore a_3 = 12