Question

The sum of squares of three numbers is 170 while the sum of products taken two at time is 157.What is sum of two numbers

Answer 1

Answer

Sum of three numbers = 22

Explanation

Let three numbers be a, b and c

It is given that,

The sum of squares of three numbers is 170

So, a^2 + b^2 + c^2 = 170

while the sum of products taken two at time is 157.

It means that ab + bc + ac = 157

we have (a + b + c)^2 = a^2 + b^2 + c^2 + 2(ab + bc + ca)

              (a + b + c)^2  = 170 + (2 x 157) =484

               a + b + c = 22

Therefore sum of three numbers is 22

Answer 2

Question:

The sum of squares of three numbers is 170 while the sum of products taken two at time is 157. What is sum of three numbers?

Solution:

Let the number be a, b and c

The sum of squares of three numbers is 170

a² + b² + c² = 170

The sum of products taken two at time is 157

ab + bc + ca = 157

(a + b + c)² = a² + b² + c² + 2(ab + bc + ca)

(a + b + c)² = 170 + 2(157)

(a + b + c)² = 484

a + b + c = √484

a + b + c = 22

Answer: The sum of the three numbers is 22