Add 42/80 and 27/21, Solve 42/80 + 1 6/21 as a fraction

Add 42/80 and 27/21

1^st number: 42/80, 2^nd number: 1 6/21

42/80 + 27/21 is 507/280.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
27/21 = 27 × 80/21 × 80 = 2160/1680
Add the two like fractions:
882/1680 + 2160/1680 = 882 + 2160/1680 = 3042/1680
3042/1680 simplified gives 507/280
So, 42/80 + 27/21 = 507/280
In mixed form: 1227/280

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