Question

Find the sum from the sixth term to the twelth term of the AP 6, 10,14 ..............., *

1 point

a) 176

b) 232

c) 266

d) 184

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Answer 1

In AP 6,10,14....

a = 6

d = 4

T6 = a +5d = 6 +20 = 26

T12 = a+11d = 6+ 44 = 50

Sum of numbers from T6 to T12 is

n( T6+T12)/2

here , from T6 to T12 we have 7 terms hence, n = 7

=> Sum = 7(26+50)/2

= 7×76/2

= 7× 38

= 266

Option (C) 266 is correct ..