Add 21/80 and 60/42, Solve 21/80 + 1 18/42 as a fraction

Add 21/80 and 60/42

1^st number: 21/80, 2^nd number: 1 18/42

21/80 + 60/42 is 947/560.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680
Likewise, for the 2nd fraction, since 42 × 40 = 1680,
60/42 = 60 × 40/42 × 40 = 2400/1680
Add the two like fractions:
441/1680 + 2400/1680 = 441 + 2400/1680 = 2841/1680
2841/1680 simplified gives 947/560
So, 21/80 + 60/42 = 947/560
In mixed form: 1387/560

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