Question

An approximate value for 5 square root 2 could be as follows:
A) 5.2
B) 7
C) 10
D) 70

Answer 1

What you can do is to square \(5\sqrt2\), which gives \(5\sqrt2=5^2(\sqrt2)^2=25\times2=50\)
Compare with the square of each of the answers, and choose the closest.