Add 90/60 and 80/21, Solve 1 30/60 + 3 17/21 as a fraction

Add 90/60 and 80/21

1^st number: 1 30/60, 2^nd number: 3 17/21

90/60 + 80/21 is 223/42.

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,
80/21 = 80 × 20/21 × 20 = 1600/420
Add the two like fractions:
630/420 + 1600/420 = 630 + 1600/420 = 2230/420
2230/420 simplified gives 223/42
So, 90/60 + 80/21 = 223/42
In mixed form: 513/42

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