Add 72/42 and 56/80, Solve 1 30/42 + 56/80 as a fraction

Add 72/42 and 56/80

1^st number: 1 30/42, 2^nd number: 56/80

72/42 + 56/80 is 169/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
72/42 = 72 × 40/42 × 40 = 2880/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
56/80 = 56 × 21/80 × 21 = 1176/1680
Add the two like fractions:
2880/1680 + 1176/1680 = 2880 + 1176/1680 = 4056/1680
4056/1680 simplified gives 169/70
So, 72/42 + 56/80 = 169/70
In mixed form: 229/70

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