Question

The common difference of two different A.P's are equal. The first term of the first progression is 3 more
than the first term of second progression. If the 7th term of first progression is 28 and gil term of second
progression is 29. then find the both different arithmetic progressions.
(Sep 2020) (5M)​

Answer 1

Answer:

For first A.P

S1n​=(2n​)(2n+(n−1)d)

S130​=(230​)(2×3+(30−1)d)

S130​=15(6+29d)

S130​=90+435d

For second AP

S2n​=(2n​)(2n+(n−1)d)

S230​=(230​)(2×8+(30−1)d)

S230​=15(16+29d)

S230​=240+435d

Difference between S130​−S230​=(90+435d)−(240+435d)=150

Step-by-step explanation: