Question

Which term of the arithmetic progression 5,15,25_ _ _ _ _ _ _ _ will be 130 more than its 31st term?

Answer 1

Using general term of an arithmetic progression

An = a + ( n-1 )d

130 + a + 30d = 5 + ( n-1)10

130 + 5 + 300 = 5 + ( n-1 )10

435 - 5 = ( n-1 )10

430 = ( n-1 )10

43 = n-1

n = 44