Question

By rounding to 1 significant figure, estimate the answer to these questions:

1) 78 x 92
2) 615 x 38
3) 423 x 764

Answer 1

To round to 1 significant figure, look at the first non-zero digit and round to that digit.

Step-by-step explanation:

In order to round to 1 significant figure, we look at the first non-zero digit in the number and round to that digit. If there are no non-zero digits before the decimal point, we count the significant figures starting from the first non-zero digit after the decimal point.

For example, in the calculation 78 x 92, we round to 1 significant figure by looking at the first non-zero digit, which is 7. The answer would be approximately 80.

Similarly, in the calculation 615 x 38, we round to 1 significant figure by looking at the first non-zero digit, which is 6. The answer would be approximately 600.

Lastly, in the calculation 423 x 764, we round to 1 significant figure by looking at the first non-zero digit, which is 4. The answer would be approximately 400.