Add 30/84 and 42/35, Solve 30/84 + 1 7/35 as a fraction

Add 30/84 and 42/35

1^st number: 30/84, 2^nd number: 1 7/35

30/84 + 42/35 is 109/70.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 35 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
30/84 = 30 × 5/84 × 5 = 150/420
Likewise, for the 2nd fraction, since 35 × 12 = 420,
42/35 = 42 × 12/35 × 12 = 504/420
Add the two like fractions:
150/420 + 504/420 = 150 + 504/420 = 654/420
654/420 simplified gives 109/70
So, 30/84 + 42/35 = 109/70
In mixed form: 139/70

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