Question

Subtract 2.5 x 10-6 from 3.9 x 10-4 to the correct significant figure.

Answer 1

Answer:

3.575×$10^{-4}$

It has 4 significant digits.

Solution:

2.5×$10^{-6}$= 0.025×$10^{-4}$

3.6×$10^{-4}$ - 0.025×$10^{-4}$

=(3.6-0.025)×$10^{-4}$

=3.575×$10^{-4}$

3, 5, 7 and 5 are significant digits in the above number.

Answer 2

Answer:

Answer:

3.575×10^{-4}10

−4

It has 4 significant digits.

Solution:

2.5×10^{-6}10

−6

= 0.025×10^{-4}10

−4

3.6×10^{-4}10

−4

- 0.025×10^{-4}10

−4

=(3.6-0.025)×10^{-4}10

−4

=3.575×10^{-4}10

−4

3, 5, 7 and 5 are significant digits in the above number.