Exams › JEE Main › Maths

How many pairs of consecutive odd natural numbers, each greater than 10, have a sum less than 40?

1. 4
2. 6
3. 3
4. 5

Correct answer: 4

Solution

The pairs of consecutive odd natural numbers greater than 10 can be represented as (11, 13), (13, 15), (15, 17), and (17, 19). Their sums are 24, 28, 32, and 36 respectively, all of which are less than 40, resulting in a total of 4 valid pairs.

Related JEE Main Maths questions

• If Sₙ = cosⁿ θ + sinⁿ θ, then the value of 3S₄ - 2S₆ is
• For a natural number n, the inequality 2^(n - 1) < nⁿ holds when
• For any natural number n, the product n(n + 1) is always
• For which positive integers n does the inequality 3ⁿ exceed n³?
• For which values of n does the inequality 4ⁿ/(n+1) < (2n)!/(n!)² hold, if P(n) denotes this statement?
• For a positive integer n, define a(n) = 1 + 1/2 + 1/3 + 1/4 +... + 1/(2ⁿ - 1). Which of the following is true?

⚔️ Practice JEE Main Maths free + battle 1v1 →