For the AP - 3, - 7, - 11, … can we find directly a30 - a20 without actually finding a30 and a20 reason for your answer.

True

Given


First term, a = - 3


Common difference, d = a2 - a1 = - 7 - (- 3) = - 4


a30 - a20 = a + 29d - (a + 19d)


= 10d


= - 40


It is so because difference between any two terms of an AP is proportional to common difference of that AP


3