To solve the problem [tex]\( 6.221 \times 7.11 - 13.7 \)[/tex], follow these steps:
1. Multiply the two numbers:
[tex]\[
6.221 \times 7.11 = 44.23131
\][/tex]
2. Subtract the given value:
[tex]\[
44.23131 - 13.7 = 30.53131
\][/tex]
3. Expressing the answer to the appropriate number of significant figures:
- The number 6.221 has 4 significant figures.
- The number 7.11 has 3 significant figures.
- In multiplication, the result should have the same number of significant figures as the number with the fewest significant figures, which is 3 in this case.
- Therefore, 44.23131 should be rounded to 3 significant figures, which makes it 44.2.
- The value 13.7 has 3 significant figures.
4. Perform the subtraction with the correct significant figures:
- Subtract 13.7 from 44.2:
[tex]\[
44.2 - 13.7 = 30.5
\][/tex]
Thus, the final answer, expressed to the correct number of significant figures, is:
[tex]\[
\boxed{30.5}
\][/tex]