Add 90/36 and 21/70, Solve 2 18/36 + 21/70 as a fraction

Add 90/36 and 21/70

1^st number: 2 18/36, 2^nd number: 21/70

90/36 + 21/70 is 14/5.

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,
90/36 = 90 × 35/36 × 35 = 3150/1260
Likewise, for the 2nd fraction, since 70 × 18 = 1260,
21/70 = 21 × 18/70 × 18 = 378/1260
Add the two like fractions:
3150/1260 + 378/1260 = 3150 + 378/1260 = 3528/1260
3528/1260 simplified gives 14/5
So, 90/36 + 21/70 = 14/5
In mixed form: 24/5

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