Add 70/4 and 21/72, Solve 17 2/4 + 21/72 as a fraction

Add 70/4 and 21/72

1^st number: 17 2/4, 2^nd number: 21/72

70/4 + 21/72 is 427/24.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 4 × 18 = 72,
70/4 = 70 × 18/4 × 18 = 1260/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72
Add the two like fractions:
1260/72 + 21/72 = 1260 + 21/72 = 1281/72
1281/72 simplified gives 427/24
So, 70/4 + 21/72 = 427/24
In mixed form: 1719/24

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