By signing in you confirm you are 18 or older, or have your parent’s or guardian’s consent.

CTET 7 Feb 2026 Paper 1, Question 31

Topic: Numbers

Q31

What is the sum of all the prime numbers between 12 and 49?

  1. (1) 299
  2. (2) 300Correct answer
  3. (3) 301
  4. (4) 302

Solution.

CBSE answer: (2)

Answer: (2) 300

  1. List the primes after 12 and before 49: 13, 17, 19, 23, 29, 31, 37, 41, 43, 47.
  2. Pair them for quick adding: 13+47=6013+47=60, 17+43=6017+43=60, 19+41=6019+41=60, 23+37=6023+37=60, 29+31=6029+31=60.
  3. Five pairs of 60 give 5×60=3005 \times 60 = 300.

Trap: missing 47 or wrongly counting 49 (7×77 \times 7) as prime changes the total.