Estimate 0.419 x 6.88 by first rounding each number to the place of its leftmost nonzero digit

Question

Estimate 0.419 x 6.88 by first rounding each number to the place of its leftmost nonzero digit

Answer 1

The instructions tell us to round 0.419 to just 0.4 and 6.88 to 7; therefore a quick -in-the-head estimate is 0.4 times 7, or around 2.8