Answer: 30 lbs, 13 oz
This converts to 493 ounces
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Step-by-step explanation:
Pumpkin A weighs 7 lb, 12 oz. Let's convert that to ounces only
1 lb = 16 oz
7 lbs = 112 oz (multiply both sides by 7)
7 lbs, 12 oz = 112 oz + 12 oz .... add 12 oz to both sides
7 lbs, 12 oz = 124 oz
Pumpkin A's weight of 7 lbs, 12 oz is the same as 124 oz
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Do something similar for pumpkin B
1 lb = 16 oz
10 lbs = 160 oz
10 lbs, 4 oz = 160 oz + 4 oz
10 lbs, 4 oz = 164 oz
Pumpkin B weighs 164 oz
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Let's convert the "2 lbs, 9 oz" to ounces only
1 lb = 16 oz
2 lbs = 32 oz
2 lbs, 9 oz = 32 oz + 9 oz
2 lbs, 9 oz = 41 oz
So pumpkin C is 41 ounces heavier compared to pumpkin B
The weight of pumpkin C is 164+41 = 205 ounces
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We have these three weights in ounces only
- Pumpkin A = 124 oz
- Pumpkin B = 164 oz
- Pumpkin C = 205 oz
Adding those three ounces only weights leads to
124+164+205 = 493 ounces
The total weight of all three pumpkins is 493 ounces
Now let's convert back to the unit "pounds, ounces"
Divide that result over 16 since there are 16 ounces per pound
493/16 = 30.8125
Ignore the decimal portion. The 30 is the quotient which means 493-30*16 = 13 is the remainder.
In other words,
493/16 = 30 remainder 13
which leads to
493 ounces = 30 pounds, 13 ounces
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As a check,
1 lb = 16 oz
30 lbs = 480 oz
30 lbs, 13 oz = 480 oz + 13 oz
30 lbs, 13 oz = 493 oz
The answer is confirmed.