Carry out each calculation and give the answer using the proper number of significant figures.
a. 3.81 × 0.046 b. 120.085/106
Analysis
Since these calculations involve multiplication and division, the answer must have the same number of significant figures as the original number with the fewest number of significant figures.
a. 3.81 × 0.046 = 0.1753
• Since 0.046 has only two significant figures, round the answer to give it two significant figures.
0.1753^{\curvearrowleft}Since this number is 5 (5 or greater),round the 7 to its left up by one.
Answer: 0.18
b. 120.085/106 = 1.132 877 36
• Since 106 has three significant figures, round the answer to give it three significant figures.
1.132 877 36^{\curvearrowleft}Since this number is 2 (4 or less),drop it and all numbers to its right.
Answer: 1.13