Skill: Estimate products

To estimate a product, replace each factor with a nearby number that is easier to multiply. Choose rounding that keeps the answer’s size reasonable.

Example: Estimate $48.7 \times 19.6$.

1. Round each factor to a friendly number:

   • $48.7$ is close to $50$.
   • $19.6$ is close to $20$.

2. Multiply the rounded numbers:

$$50 \times 20 = 1{,}000$$

So,

$$48.7 \times 19.6 \approx 1{,}000$$

The symbol $\approx$ means “approximately equal to.” The estimated product is about 1,000. This gives you a quick benchmark: an exact answer should be close to 1,000, not 100 or 10,000.