Add 81/60 and 5/28, Solve 1 21/60 + 5/28 as a fraction

Add 81/60 and 5/28

1^st number: 1 21/60, 2^nd number: 5/28

81/60 + 5/28 is 107/70.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
81/60 = 81 × 7/60 × 7 = 567/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
5/28 = 5 × 15/28 × 15 = 75/420
Add the two like fractions:
567/420 + 75/420 = 567 + 75/420 = 642/420
642/420 simplified gives 107/70
So, 81/60 + 5/28 = 107/70
In mixed form: 137/70

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