College

Perform this calculation to the correct number of significant figures:

[tex]78.222 \times (12.02 - 11.52)[/tex]

A. 39
B. 39.1
C. 39.11
D. 39.111
E. None of these

Answer :

To solve the problem and determine the correct answer with the appropriate number of significant figures, follow these steps:

1. Perform the Calculation Inside the Parentheses:

We start by calculating the expression inside the parentheses:

[tex]\[
12.02 - 11.52 = 0.50
\][/tex]

In this subtraction, both numbers (12.02 and 11.52) have two decimal places, resulting in the answer having two decimal places as well.

2. Multiply the Result by 78.222:

Next, multiply the result from step 1 by 78.222:

[tex]\[
78.222 \times 0.50 = 39.111
\][/tex]

3. Determine the Correct Number of Significant Figures:

In multiplication, the number of significant figures in the result is determined by the number in the calculation with the fewest significant figures. The numbers are:

- 78.222 has 5 significant figures.
- 0.50 has 2 significant figures.

Therefore, the result must be expressed with 2 significant figures.

4. Round the Result:

Round 39.111 to 2 significant figures:

[tex]\[
39.111 \approx 39
\][/tex]

5. Select the Correct Answer:

The correctly rounded result, based on significant figures, is 39. Therefore, the answer to the question is:

39