Question

Perform this mathematical operation and express the answer to the correct number of significant figures: 1.285 x 10-2 - 1.24 x 10-3 A) 0.01161 B) 1.16 x 10-2 C) 1.16 x 102 D) 1.59 x 10-5​

Answer 1

B)

Explanation:

`1.24*10^{-3) = 1.24 * 10^(-1)*10^(-2) = 0.124 * 10^(-2)`

`1.285*10^(-2) - 1.24*10^(-3)=1.285*10^(-2) -0.124*10^(-2)\\\\ = (1.285 - 0.124)*10^(-2)\\\\= 1.161 *10^{-2)\\\\= 1.16 *10^(-2)`