To estimate the product of 39 × 71 by rounding each factor to the nearest ten, follow these steps:

1. Round the first factor (39): The nearest ten is 40.
2. Round the second factor (71): The nearest ten is 70.

Now, multiply the rounded values:

[

40 times 70 = 2800

]

So, the product of 39 × 71 is approximately 2800.

This estimation simplifies calculations and gives a quick idea of the size of the actual product. If you have further questions or need deeper insight, feel free to ask!