Question

Briana has 4 1/2 cups of oats. She uses 2 1/4 cups of oats to make oatmeal- raisins cookies, then borrow 1 cup of oats from her neighbor. Her recipe for granola calls 2 1/2 cups of oats. Does she have enough? How much will she have left over, or how much more will she need?

Answer 1

Answer:

She has enough with $\frac{3}{4}$ cups left over.

Step-by-step explanation:

For this equation, it's probably easiest to use improper fractions.

At the start, she has 4$\frac{1}{2}$ cups, or $\frac{9}{2}$, which can be converted to $\frac{18}{4}$ (which is useful for the next part) by multiplying the numerator and denominator by 2.

When she uses 2$\frac{1}{4}$ cups, which can be converted to $\frac{9}{4}$. When subtracting this from the original, you get $\frac{18}{4}$-$\frac{9}{4}$=$\frac{9}{4}$.

She borrows another cup, or $\frac{4}{4}$ of a cup, which gets added on to the previous result, giving $\frac{9}{4}$+ $\frac{4}{4}$=$\frac{13}{4}$.

The recipe calls for 2$\frac{1}{2}$ cups, which can be converted to $\frac{5}{2}$ or $\frac{10}{4}$.

$\frac{13}{4}$-$\frac{10}{4}$=$\frac{3}{4}$, meaning she has $\frac{3}{4}$ cups left over.

** solving this mainly uses conversion to improper fractions and adding/subtracting fractions, which may be skills you would like to practice. I'm always happy to help!