On Monday, Leo memorizes $\frac{3}{5}$ of his trumpet solo. On Tuesday, he memorizes $\frac{1}{3}$ more. What fraction of his solo does he have left to memorize?
Fraction comparison and addition
2
$\begingroup$
arithmetic
fractions
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1 Answers
4
To be able to compare fractions, it is helpful to find a common denominator. The denominators are $3$ and $5$, so $3 \cdot 5 = 15$ is a good choice for a common denominator.
If we want to rewrite $\frac{3}{5}$ with a denominator of $15$, we should multiply the top and bottom by $3$. Doing so shows us that $\frac{3}{5}$ is the same as $\frac{9}{15}$.
Similarly, we can turn $\frac{1}{3}$ into $\frac{5}{15}$ (multiply the top and bottom by $5$ this time).
Now the problem can be read differently. Imagine his trumpet solo is broken into $15$ parts. He memorized $9$ parts on the first day and $5$ parts on the second day. This means he has memorized $14$ of the $15$ total parts, and so has $1$ part out of $15$ (or $\frac{1}{15}$) remaining to learn.