3/5 of 1600 = $960 spent for heavy duty tapes
1600 - 960 = $640 spent for regular tapes
The company normally bought
960 ÷ 30 = 32 heavy duty tapes
640 ÷ 20 = 32 regular tapes
With the new prices, the company is paying
32 × 28 = 896 for the heavy duty tapes
32 × 19 = 608 for the regular tapes
The company is saving
960 - 896 = $64 for the heavy duty tapes
640 - 608 = $32 for the regular tapes