Add 72/45 and 21/70, Solve 1 27/45 + 21/70 as a fraction

Add 72/45 and 21/70

1^st number: 1 27/45, 2^nd number: 21/70

72/45 + 21/70 is 19/10.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
72/45 = 72 × 14/45 × 14 = 1008/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630
Add the two like fractions:
1008/630 + 189/630 = 1008 + 189/630 = 1197/630
1197/630 simplified gives 19/10
So, 72/45 + 21/70 = 19/10
In mixed form: 19/10

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