Add 90/70 and 70/84, Solve 1 20/70 + 70/84 as a fraction

Add 90/70 and 70/84

1^st number: 1 20/70, 2^nd number: 70/84

90/70 + 70/84 is 89/42.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420
Add the two like fractions:
540/420 + 350/420 = 540 + 350/420 = 890/420
890/420 simplified gives 89/42
So, 90/70 + 70/84 = 89/42
In mixed form: 25/42

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