Add 21/15 and 27/80, Solve 1 6/15 + 27/80 as a fraction

Add 21/15 and 27/80

1^st number: 1 6/15, 2^nd number: 27/80

21/15 + 27/80 is 139/80.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 15 × 16 = 240,
21/15 = 21 × 16/15 × 16 = 336/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
27/80 = 27 × 3/80 × 3 = 81/240
Add the two like fractions:
336/240 + 81/240 = 336 + 81/240 = 417/240
417/240 simplified gives 139/80
So, 21/15 + 27/80 = 139/80
In mixed form: 159/80

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