Evaluate ab for a = 2 3/4 and b = 4/5

Estimate the product. round the first factor to the nearest whole number, round the second factor to the nearest ten, and then multiply. 3 8/9 × 96

Apackage of five erasers cost 0. $.39 at this rate how many how much would 60 erasers cost in dollars and cents

Given that sin∅ = 1/4, 0 < ∅ < π/2, what is the exact value of cos∅? a. (√4)/4 b. (√15)/4 c. (4π)/2 d. (4√2)/4