Add 70/49 and 81/80, Solve 1 21/49 + 1 1/80 as a fraction

Add 70/49 and 81/80

1^st number: 1 21/49, 2^nd number: 1 1/80

70/49 + 81/80 is 1367/560.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 80 is 3920

Next, find the equivalent fraction of both fractional numbers with denominator 3920
For the 1st fraction, since 49 × 80 = 3920,
70/49 = 70 × 80/49 × 80 = 5600/3920
Likewise, for the 2nd fraction, since 80 × 49 = 3920,
81/80 = 81 × 49/80 × 49 = 3969/3920
Add the two like fractions:
5600/3920 + 3969/3920 = 5600 + 3969/3920 = 9569/3920
9569/3920 simplified gives 1367/560
So, 70/49 + 81/80 = 1367/560
In mixed form: 2247/560

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