Answer: 19.99
Step-by-step explanation
Method 1
Gavin saves 20% so he pays the remaining 80%
80% of 24.99 = 0.80*24.99 = 19.992 = 19.99
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Method 2
Gavin saves 20%, so he saves 0.20*24.99 = 4.998 = 5.00
The final price is therefore 24.99 - 5.00 = 19.99