Add 90/60 and 8/21, Solve 1 30/60 + 8/21 as a fraction

Add 90/60 and 8/21

1^st number: 1 30/60, 2^nd number: 8/21

90/60 + 8/21 is 79/42.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
90/60 = 90 × 7/60 × 7 = 630/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
8/21 = 8 × 20/21 × 20 = 160/420
Add the two like fractions:
630/420 + 160/420 = 630 + 160/420 = 790/420
790/420 simplified gives 79/42
So, 90/60 + 8/21 = 79/42
In mixed form: 137/42

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