Add 28/36 and 90/70, Solve 28/36 + 1 20/70 as a fraction

Add 28/36 and 90/70

1^st number: 28/36, 2^nd number: 1 20/70

28/36 + 90/70 is 130/63.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 70 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 36 × 35 = 1260,
28/36 = 28 × 35/36 × 35 = 980/1260
Likewise, for the 2nd fraction, since 70 × 18 = 1260,
90/70 = 90 × 18/70 × 18 = 1620/1260
Add the two like fractions:
980/1260 + 1620/1260 = 980 + 1620/1260 = 2600/1260
2600/1260 simplified gives 130/63
So, 28/36 + 90/70 = 130/63
In mixed form: 24/63

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