What is the estimated value of the length of a square with an area of 200 square inches?

The estimated value of the length of a square with an area of 200 square inches is about 14.14 inches

area of a square is S^2

so to estimate think of a number when multiplied by itself would equal 200

think about 10, 10 x 10 = 100 too low

20 x 20 = 400, too high

so 15 x 15 = 225, pretty close

so try 14, 14 x 14 = 196

so the actual value is a little over 14

so 14 would be the right estimate