Add 70/21 and 80/60, Solve 3 7/21 + 1 20/60 as a fraction

Add 70/21 and 80/60

1^st number: 3 7/21, 2^nd number: 1 20/60

70/21 + 80/60 is 14/3.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
70/21 = 70 × 20/21 × 20 = 1400/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
80/60 = 80 × 7/60 × 7 = 560/420
Add the two like fractions:
1400/420 + 560/420 = 1400 + 560/420 = 1960/420
1960/420 simplified gives 14/3
So, 70/21 + 80/60 = 14/3
In mixed form: 42/3

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