In both of these problems you are asked to find a percentage of another number and then add it to that number... In math
"is" means =
"of" means ×
1) In the first problem 20% of 100 is, means
20% × 100 =
.20 × 100 = $20
now add it to the cost of the meal.
100 + 20 = $120 (final cost)
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2) In the second problem 5% of 12300 is, means
5% × 12300 =
.05 × 12300 = $615
add this to the original price for the final cost...
12300 + 615 = $12,915