Add 70/42 and 21/30, Solve 1 28/42 + 21/30 as a fraction

Add 70/42 and 21/30

1^st number: 1 28/42, 2^nd number: 21/30

70/42 + 21/30 is 71/30.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
70/42 = 70 × 5/42 × 5 = 350/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Add the two like fractions:
350/210 + 147/210 = 350 + 147/210 = 497/210
497/210 simplified gives 71/30
So, 70/42 + 21/30 = 71/30
In mixed form: 211/30

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