Final answer:
The approximate calculation of 6.8 x 13.9 + 155.5 is 250 when rounded to two significant figures, factoring in the precision of the original values.
Step-by-step explanation:
To approximate the calculation 6.8 x 13.9 + 155.5, we first perform the multiplication and then add 155.5.
- Multiply 6.8 by 13.9 to get 94.52.
- Add 155.5 to 94.52 to get a total of 250.02.
However, when dealing with significant figures, we have to round our answer to the least precise measurement in our original calculation. The number 6.8 has two significant figures, and the number 13.9 has three significant figures, so our final answer should be rounded to two significant figures because 6.8 is the least precise measurement. Therefore, 6.8 x 13.9 + 155.5 is approximately 250 when rounded to two significant figures.