You can put this solution on YOUR website! You can solve this in steps:
1/2 of the recipe would be 3/7 of a cup
This is the same as 6/14 of a cup
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1/4 of the recipe would be half of this, or
3/14 of a cup
This is the same as 6/28
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1/8 of the recipe would be 1/2 of this, or
3/28 of a cup
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3/8 of the recipe would be 3 times this, or
9/28 of a cup
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Or, you can do it in 3 steps:
9/28 of a cup is needed