Add 21/60 and 90/7, Solve 21/60 + 12 6/7 as a fraction

Add 21/60 and 90/7

1^st number: 21/60, 2^nd number: 12 6/7

21/60 + 90/7 is 1849/140.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 7 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
21/60 = 21 × 7/60 × 7 = 147/420
Likewise, for the 2nd fraction, since 7 × 60 = 420,
90/7 = 90 × 60/7 × 60 = 5400/420
Add the two like fractions:
147/420 + 5400/420 = 147 + 5400/420 = 5547/420
5547/420 simplified gives 1849/140
So, 21/60 + 90/7 = 1849/140
In mixed form: 1329/140

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