Question
Find the sum:
$3+1\frac{4}{15}+1\frac{3}{20}$
$3+1\frac{4}{15}+1\frac{3}{20}$
✓
Answer
We have,
$L.C.M$. of $15$ and $20 = (2 \times 2 \times 3 \times 5) = 60$
$\begin{array}{c|c}5&15,20\\\hline3&3,4\ \ \ \ \\\hline2&1,4\ \ \ \ \\\hline2&1,2\ \ \ \ \ \\\hline&1,1\ \ \ \ \ \end{array} $
Therefore,
$3+1\frac{4}{15}+1\frac{3}{20}$
$=\frac{3}{1}+\frac{19}{15}+\frac{23}{20}$
$=\frac{(180+76+69)}{60}$
$\Big(\frac{60}{1}=60,60\times3=180\Big)$
$\Big(\frac{60}{15}=4,4\times19=76\Big)$
and $\Big(\frac{60}{20}=3,3\times23=69\Big)$
$=\frac{325}{60}$
$=\frac{65}{12}$
$=5\frac{5}{12}$
$L.C.M$. of $15$ and $20 = (2 \times 2 \times 3 \times 5) = 60$
$\begin{array}{c|c}5&15,20\\\hline3&3,4\ \ \ \ \\\hline2&1,4\ \ \ \ \\\hline2&1,2\ \ \ \ \ \\\hline&1,1\ \ \ \ \ \end{array} $
Therefore,
$3+1\frac{4}{15}+1\frac{3}{20}$
$=\frac{3}{1}+\frac{19}{15}+\frac{23}{20}$
$=\frac{(180+76+69)}{60}$
$\Big(\frac{60}{1}=60,60\times3=180\Big)$
$\Big(\frac{60}{15}=4,4\times19=76\Big)$
and $\Big(\frac{60}{20}=3,3\times23=69\Big)$
$=\frac{325}{60}$
$=\frac{65}{12}$
$=5\frac{5}{12}$
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