Add 90/21 and 21/70, Solve 4 6/21 + 21/70 as a fraction

Add 90/21 and 21/70

1^st number: 4 6/21, 2^nd number: 21/70

90/21 + 21/70 is 321/70.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
90/21 = 90 × 10/21 × 10 = 900/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210
Add the two like fractions:
900/210 + 63/210 = 900 + 63/210 = 963/210
963/210 simplified gives 321/70
So, 90/21 + 21/70 = 321/70
In mixed form: 441/70

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