CA Foundation · Quantitative Aptitude · Equations
The product of two consecutive positive odd integers is 143. What is the sum of these two integers?
The sum is 24. Taking the odd integers as x and x+2 gives x²+2x−143=0, so x=11 and the numbers are 11 and 13. Their product is 143 and their sum is 24. The negative root is rejected because the integers are positive.
- A22
- B24Correct
- C26
- D20
Explanation
Let the integers be x and x+2. Then x(x+2)=143, so x²+2x−143=0, which factorises as (x+13)(x−11)=0. The positive value is x=11, so the integers are 11 and 13, with sum 24. Check: 11×13=143. The sum 22 would come from 10+12, which are even and give 120.
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