Question

If the common difference of an Ap is 4 then value of a25-a20 is ?

Answer 1

Answer:

20

Step-by-step explanation:

Let the common difference and first term be 'd' and 'a'.

⇒ a₂₅ - a₂₀

⇒ [a + (25 - 1)d] - [a + (20 - 1)d]

⇒ [a + 24d] - [a + 19d]

⇒ a + 24d - a - 19d

⇒ 24d - 19d

⇒ 5d

⇒ 5(4)         [given, d = 4]

⇒ 20

Answer 2

Answer:

Answer is 20

Step-by-step explanation:

a25= a + 24d (1)

a20= a + 19d (2)

(1)-(2)

= 5d

=5*(4)

=20