Question

1. (2 points) round each of the following numbers to four significant digits.

a. 27.951034
b. 0.000148752
c. ( 31.002761 \times 10^{-5} )
d. 89.99603
e. 39,004
f. -700.9852

Explanation:

Step1: Round a to 4 sig figs

Identify first 4 sig figs, round the 4th: $27.951034
ightarrow 27.95$

Step2: Round b to 4 sig figs

Ignore leading zeros, round 4th sig fig: $0.000148752
ightarrow 0.0001488$

Step3: Round c to 4 sig figs

Round coefficient to 4 sig figs: $31.002761 \times 10^{-5}
ightarrow 31.00 \times 10^{-5}$

Step4: Round d to 4 sig figs

Identify first 4 sig figs, round 4th: $89.99603
ightarrow 90.00$

Step5: Round e to 4 sig figs

Identify first 4 sig figs, add placeholder: $39,004
ightarrow 39,000$

Step6: Round f to 4 sig figs

Identify first 4 sig figs, round 4th: $-700.9852
ightarrow -701.0$

Answer:

a. 27.95
b. 0.0001488
c. $31.00 \times 10^{-5}$
d. 90.00
e. 39,000
f. -701.0