Question

Here's A Question!!
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The third term of an AP is 1/5 and fifth term is 1/3. Show that sum of 15 terms of AP is 8.
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Answer 1

Hey mate

here is your answer

A3 = a+2d = 1/5............i

A5= a+4d= 1/3.............ii

substract i from ii

2d= 1/3-1/5

2d= 5-3/15

d=2/15*1/2

d=1/15

put in i

a+2/15=1/5

a= 3-2/15

a=1/15

find s15

$= \frac{15}{2} (2 \times \frac{1}{15} + (15 - 1) \times \frac{1}{15} ) \\ = \frac{15}{2} ( \frac{2}{15} + \frac{14}{15} ) \\ = \frac{15}{2} \times \frac{16}{15} \\ = \frac{16}{2} = 8$

hence proved..

hope it helps you

plzz mark as brainliest answer

Answer 2

Answer:

$\huge{\fbox{\fbox{\bigstar{\mathfrak{\red{Answer}}}}}}$

a+2d=1/5 - a+4d=1/3

=-2d=-2/15

=d=1/15

a=1/15

a15=1/15+14×1/15

a15=1

s15=n/2 (a+a15)

=15/2 (1/15+1)

=8