Question

Mary bought 3$\frac{1}{2}$ m of lace. She used 1$\frac{3}{4}$ m of lace for her new dress. How much lace is left with her?

Answer 1

Given that

Mary bought lace of length = 3$\frac{1}{2}$ m
and lace used for new dress = 1$\frac{3}{4}$ m
In order to find the lace left with her, we will subtract 1$\frac{3}{4}$ m from 3$\frac{1}{2}$ m.

We can express a mixed fraction as an improper fraction as $\frac{(\text{Whole}\times \text{Denominator})\text{+ Numerator}}{\text{Denominator}}$.

$\therefore 3\frac{1}{2}=\frac{3\times 2+1}{2}=\frac{7}{2}$

$\therefore 1\frac{3}{4}=\frac{1\times 4+3}{4}=\frac{7}{4}$
The denomionator of both the fractions are different. So, to make it equal $\frac{7}{2}$ will multiply by $\frac{2}{2}$ to become $\frac{14}{4}$

$\therefore 3\frac{1}{2}-1\frac{3}{4}=\frac{14}{4}-\frac{7}{4}=\frac{14-7}{4}=\frac{7}{4}=1\frac{3}{4}$

So, 1$\frac{3}{4}$ m lace is left with her.