Add 90/60 and 70/21, Solve 1 30/60 + 3 7/21 as a fraction

Add 90/60 and 70/21

1^st number: 1 30/60, 2^nd number: 3 7/21

90/60 + 70/21 is 29/6.

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,
70/21 = 70 × 20/21 × 20 = 1400/420
Add the two like fractions:
630/420 + 1400/420 = 630 + 1400/420 = 2030/420
2030/420 simplified gives 29/6
So, 90/60 + 70/21 = 29/6
In mixed form: 45/6

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