Add 70/84 and 81/80, Solve 70/84 + 1 1/80 as a fraction

Add 70/84 and 81/80

1^st number: 70/84, 2^nd number: 1 1/80

70/84 + 81/80 is 443/240.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 84 × 20 = 1680,
70/84 = 70 × 20/84 × 20 = 1400/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680
Add the two like fractions:
1400/1680 + 1701/1680 = 1400 + 1701/1680 = 3101/1680
3101/1680 simplified gives 443/240
So, 70/84 + 81/80 = 443/240
In mixed form: 1203/240

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