Question

Solve the problems. Express your answers to the correct number of significant figures.

(2.08x103) (3.11x102)=
x105

Answer 1

6.47 x 10⁵.

Step-by-step explanation:

• Rules for counting for multiplication or division:

The results are reported to the fewest significant figures.

• (2.08 x 10³) has 3 significant figures.

• (3.11 x 10²) has 2 significant figures.

So, the result should has 3 significant figures:

(2.08 x 10³)(3.11 x 10²) = 6.4688 x 10⁵.

• To obtain the result with only 3 significant figures, we should use rules for rounding :

• In a series of calculations, carry the extra digits through to the final result, then round.

• If the digit to be removed :

✓ is less than 5, the preceding digit stays the same.

For example, 1.33 rounds to 1.3.

✓ is equal to or greater than 5, the preceding digit is

increased by 1. For example, 1.36 rounds to 1.4.

So, the result will be 6.4688 x 10⁵ = 6.47 x 10⁵.