Add 15/80 and 90/42, Solve 15/80 + 2 6/42 as a fraction

Add 15/80 and 90/42

1^st number: 15/80, 2^nd number: 2 6/42

15/80 + 90/42 is 261/112.

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,
90/42 = 90 × 40/42 × 40 = 3600/1680
Add the two like fractions:
315/1680 + 3600/1680 = 315 + 3600/1680 = 3915/1680
3915/1680 simplified gives 261/112
So, 15/80 + 90/42 = 261/112
In mixed form: 237/112

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