Add 42/27 and 21/80, Solve 1 15/27 + 21/80 as a fraction

Add 42/27 and 21/80

1^st number: 1 15/27, 2^nd number: 21/80

42/27 + 21/80 is 1309/720.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 80 is 2160

Next, find the equivalent fraction of both fractional numbers with denominator 2160
For the 1st fraction, since 27 × 80 = 2160,
42/27 = 42 × 80/27 × 80 = 3360/2160
Likewise, for the 2nd fraction, since 80 × 27 = 2160,
21/80 = 21 × 27/80 × 27 = 567/2160
Add the two like fractions:
3360/2160 + 567/2160 = 3360 + 567/2160 = 3927/2160
3927/2160 simplified gives 1309/720
So, 42/27 + 21/80 = 1309/720
In mixed form: 1589/720

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