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

Add 21/14 and 21/80

1^st number: 1 7/14, 2^nd number: 21/80

21/14 + 21/80 is 141/80.

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,
21/80 = 21 × 7/80 × 7 = 147/560
Add the two like fractions:
840/560 + 147/560 = 840 + 147/560 = 987/560
987/560 simplified gives 141/80
So, 21/14 + 21/80 = 141/80
In mixed form: 161/80

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