Add 72/90 and 81/70, Solve 72/90 + 1 11/70 as a fraction

Add 72/90 and 81/70

1^st number: 72/90, 2^nd number: 1 11/70

72/90 + 81/70 is 137/70.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630
Add the two like fractions:
504/630 + 729/630 = 504 + 729/630 = 1233/630
1233/630 simplified gives 137/70
So, 72/90 + 81/70 = 137/70
In mixed form: 167/70

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