The approximate difference between √10 and √15, obtained by using a calculator is; -0.7
How the approximate difference is calculated
The square root of 10 is approximately 3.162278
√(10) ≈ 3.162278
The square root of 15 is approximately 3.8729833
√(15) ≈ 3.8729833
The difference between these two values is therefore;
√(10) - √(15) ≈ 3.162278 - 3.8729833
3.162278 - 3.8729833 = -0.7107053
The difference is approximately -0.7107053. If we round this to the nearest tenth, we get -0.7. So, the approximate difference in tenths between the square root of 10 and the square root of 15 is -0.7