Carry out the following operations, and express the answer with the appropriate number of significant figures.
1.)[(285.3 multiplied by 105) - (1.500 multiplied by 103)] multiplied by 2.8948
2.) 874 multiplied by [1267 - (3.50 multiplied by 128)]
*I know what significant figures are but I am constantly getting my answers wrong for both questions. Help, please??
Follow these rules.
http://www.chemteam.info/SigFigs/SigFigs.html
Sure! Let's solve each operation step-by-step and then apply the rules for significant figures to determine the appropriate number of significant figures in the final answer.
1.) [(285.3 multiplied by 105) - (1.500 multiplied by 103)] multiplied by 2.8948
Step 1: Evaluate the expressions inside the parentheses.
= [(29993.5) - (1545)]
= [28448.5]
Step 2: Multiply the result from Step 1 by 2.8948.
= 28448.5 multiplied by 2.8948
= 82372.5326
Now, let's determine the appropriate number of significant figures. The rule for multiplication (or division) is to round the answer to the same number of significant figures as the measurement with the fewest significant figures.
In this case, the measurement with the fewest significant figures is "2.8948", which has 5 significant figures.
Thus, the final answer, expressed with the appropriate number of significant figures, is 82370 (to five significant figures).
2.) 874 multiplied by [1267 - (3.50 multiplied by 128)]
Step 1: Evaluate the expression inside the parentheses.
= [1267 - (448)]
= [819]
Step 2: Multiply the result from Step 1 by 874.
= 819 multiplied by 874
= 715806
Now, let's determine the appropriate number of significant figures. The rule for multiplication (or division) is to round the answer to the same number of significant figures as the measurement with the fewest significant figures.
In this case, the measurement with the fewest significant figures is "874", which has 3 significant figures.
Thus, the final answer, expressed with the appropriate number of significant figures, is 716000 (to three significant figures).