Let p = the number of pennies
let q = the number of quarters
p + q = 23
0.01p + 0.25q = 3.11
A=1/2ab
Replace the variables with their value
15=1/2(3/2)b
Multiply 1/2 and 3/2

15=3/4b
Divide 3/4 on both sides
15/(3/4) is the same thing as

45/4=b
Answer:
Step-by-step explanation:
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We know that Scott has put 6 rows with 5 stickers each.
The total number of stickers available with Scott = 5*6 = 30 stickers
These 30 stickers are now placed in 5 rows with equal number of stickers in each row.
Number of stickers in each row= Total number of stickers available/number of rows
Number of stickers in each row = 30/5 = 6 stickers
Number of stickers in each row now would be = 6 stickers