x

Quantitative - Mathematics - Word Problems:

Number System - All NUMBERS on the Tests

MCQ - 44-12811

Question:

The sum of the squares of three numbers is 138, while the sum of their products taken two at a time is 131. Their sum is

  1. 15
  2. 20
  3. 25
  4. 20

Correct Answer: B

Explanation:

Let the numbers be a, b and c.
Then, a2 + b2 + c2 = 138
and (ab + bc + ca) = 131
(a + b + c)2 = a2 + b2 + c2 + 2(ab+bc+ca)
(a + b + c)2 = 138 + 2 x 131 = 400
(a+b+c)2 = 400
(a + b + c) = 400 =20.

Record Performance

1297 MCQ for effective preparation of the test of Number System - All NUMBERS on the Tests of Word Problems section.

Read the MCQ statement: The sum of the squares of three numbers is 138, while the sum of their products taken two at a time is 131. Their sum is , keenly and apply the method you have learn through the video lessons for Number System - All NUMBERS on the Tests to give the answer. Record your answer and check its correct answer and video explanation for MCQ No. 44-12811.

How to Answer

Solve the question for MCQ No. and decide which option (A through D/E) is the best choice to answer the MCQ, then click/tap the blue button to view the correct answer and it explanation.

Share This Page