Question

Product of 7.69×5 be greater or less than its estimate of 8×5?

Answer 1

The product is a bit less than the estimate. In fact, 7.69 is less than 8, and if you start with an equality, i.e.

$7.69 < 8$

you can multiply both sides by a positive number, and the inequality will still hold:

$7.69 \cdot 5 < 8 \cdot 5$