Add 72/63 and 90/70, Solve 1 9/63 + 1 20/70 as a fraction

Add 72/63 and 90/70

1^st number: 1 9/63, 2^nd number: 1 20/70

72/63 + 90/70 is 17/7.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 63 × 10 = 630,
72/63 = 72 × 10/63 × 10 = 720/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Add the two like fractions:
720/630 + 810/630 = 720 + 810/630 = 1530/630
1530/630 simplified gives 17/7
So, 72/63 + 90/70 = 17/7
In mixed form: 23/7

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