Add 21/60 and 98/70, Solve 21/60 + 1 28/70 as a fraction

Add 21/60 and 98/70

1^st number: 21/60, 2^nd number: 1 28/70

21/60 + 98/70 is 7/4.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 70 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 70 × 6 = 420,
98/70 = 98 × 6/70 × 6 = 588/420
Add the two like fractions:
147/420 + 588/420 = 147 + 588/420 = 735/420
735/420 simplified gives 7/4
So, 21/60 + 98/70 = 7/4
In mixed form: 13/4

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