Question
Find the sum of all two digit numbers which when divided by 4, yields 1 as remainder.
Solution
The two-digit numbers, which when divided by 4, yield 1 as remainder, are
13, 17, … 97.
This series forms an A.P. with first term 13 and common difference 4.
Let n be the number of terms of the A.P.
It is known that the nth term of an A.P. is given by, an = a + (n –1) d
∴97 = 13 + (n –1) (4)
⇒ 4 (n –1) = 84
⇒ n – 1 = 21
⇒ n = 22
Sum of n terms of an A.P. is given by,
Is there an error in this question or solution?
Solution Find the Sum of All Two Digit Numbers Which When Divided by 4, Yields 1 as Remainder. Concept: Arithmetic Progression (A.P.).
