Answer:
y=20x+10
Step-by-step explanation:
Given:
Donald has x $20 bills and 1 $10 bills.
Let y be the total amount Donald has.
To calculate his total, we multiply the value of each bill by its frequency then sum:
[tex]y=x\times 20+1\times 10\\\\=20x+10[/tex]
Hence, the expression of Donald's total is given as y=20x+10
