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.
[tex] 7.69 < 8 [/tex]
you can multiply both sides by a positive number, and the inequality will still hold:
[tex] 7.69 \cdot 5 < 8 \cdot 5 [/tex]
