Add 15/80 and 70/42, Solve 15/80 + 1 28/42 as a fraction

Add 15/80 and 70/42

1^st number: 15/80, 2^nd number: 1 28/42

15/80 + 70/42 is 89/48.

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,
15/80 = 15 × 21/80 × 21 = 315/1680
Likewise, for the 2nd fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680
Add the two like fractions:
315/1680 + 2800/1680 = 315 + 2800/1680 = 3115/1680
3115/1680 simplified gives 89/48
So, 15/80 + 70/42 = 89/48
In mixed form: 141/48

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