Answer: 72 ounces
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Step-by-step explanation:
He uses 3/8 of the amount to make bread, 1/6 of the amount to make pancakes, and 5/12 of the amount to make jam.
Add up those fractions. But first let's make each fraction have the LCD (lowest common denominator) of 24
3/8 = 9/24 .... multiply top and bottom by 3
1/6 = 4/24 .... multiply top and bottom by 4
5/12 = 10/24 .... multiply top and bottom by 2
Now we can add the fractions:
(3/8) + (1/6) + (5/12)
(9/24) + (4/24) + (10/24)
(9+4+10)/24
23/24
So in total, Wayne used up 23/24 of all the blueberries he bought.
Let's make this unknown amount x
x = amount of blueberries he bought, in ounces
Multiplying the sum we got (23/24) by x leads to the amount of blueberries he used, which is 69 ounces
So,
(fraction used)*(amount he bought) = (amount he used)
(23/24)*x = 69
23x = 69*24 .... multiply both sides by 24
23x = 1656
x = 1656/23 ... divide both sides by 23
x = 72
He bought 72 ounces of blueberries.
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Let's check that answer
A = 3/8 of 72 = (3/8)*72 = 27 = amount used for bread
B = 1/6 of 72 = (1/6)*72 = 12 = amount used for pancakes
C = 5/12 of 72 = (5/12)*72 = 30 = amount used for jam
A+B+C = 27+12+30 = 69 = total amount used
This confirms our answer.