Add 21/14 and 3/80, Solve 1 7/14 + 3/80 as a fraction

Add 21/14 and 3/80

1^st number: 1 7/14, 2^nd number: 3/80

21/14 + 3/80 is 123/80.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 80 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 14 × 40 = 560,
21/14 = 21 × 40/14 × 40 = 840/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
3/80 = 3 × 7/80 × 7 = 21/560
Add the two like fractions:
840/560 + 21/560 = 840 + 21/560 = 861/560
861/560 simplified gives 123/80
So, 21/14 + 3/80 = 123/80
In mixed form: 143/80

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