Question

Find the sum of: 34 + 32 + 30 +.......+10

Answer 1

Please see the attachment

Answer 2

Sum of the series = 286

Step-by-step explanation:

34 + 32 + 30 + 28 +..... +10

Beginning of the series = 34

End of series = 10

Difference = 2

T = a + (n-1) d

10 = 34 + (n - 1)(-2)

-24 / -2 = n - 1

12 = n - 1

So n = 13

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

= 13 / 2[ 2*34 + 12*(-2)]

= 13 / 2 * 22

= 286