Answer:
Step-by-step explanation:
Let p represent the number of pens Nick sold. Then the revenue is ...
0.10p +0.05(1000 -p) = 74.50
0.05p = 24.50 . . . . . . eliminate parentheses, subtract 50
p = 490 . . . . . . . . . . . . multiply by 20
The number of pencils sold is then ...
pencils = 1000 -490 = 510
Nick's Printing Press sold 490 pens and 510 pencils.