(C) 7/10 cup is the correct answer
Step-by-step explanation:
First of all we will calculate the 40% of grandmother's recipe then add it to the given flour in grandma's recipe
So,
The amount of flour in grandma's recipe = F_g = 1/2 cups
Calculating percentage
[tex]=40\%\ of\ \frac{1}{2}\\=\frac{40}{100}*\frac{1}{2}\\=\frac{2}{10}[/tex]
So Evelyn needs to add 2/10 cups more to the original quantity.
So,
Flour used by Evelyn:
[tex]=\frac{1}{2}+\frac{2}{10}\\\\=\frac{5+2}{10}\\\\=\frac{7}{10}\ cups[/tex]
Hence,
(C) 7/10 cup is the correct answer
Keywords: Percentage, Quantity
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