Name: lanette Roessler
Who is asking: Parent
Level: Middle

Question:
Find the number of 3/4 pound of sunflower seeds that can be filled with 225 pounds of sunflower seeds the answer is 300 but how did they arrive at that number we did 3/4. 225/1= that was wrong we tried 3/4.1/225= that was wrong then 3/4 divided by 225/1 that was wrong. What are we doing wrong?

Hi,

Imagine a 255 pound sack of sunflower seeds from which you want to fill boxes that contain 3/4 pounds. Since each box holds 3/4 pounds, two boxes will contain 1 1/2 pounds and 4 boxes will contain 3 pounds. Think of the process in two steps; first divide the 225 pounds into 3 pound lots and then use each 3 pound lot to fill 4 boxes. Since 225/3 = 75, there are 75, 3 pound lots. Hence you can fill 75 x 4 = 300 boxes. (What you have done is calculate 225 x 4/3.)

Another way to approach this problem is to think in terms of the units. You have 225 pounds, 3/4 pounds per box and the units of the answer is boxes. Since

"pounds x boxes/pound = boxes"

calculate 225 x 4/3 = 300 boxes.

Cheers,
Penny
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