Add 21/84 and 90/10, Solve 21/84 + 9 0/10 as a fraction

Add 21/84 and 90/10

1^st number: 21/84, 2^nd number: 9 0/10

21/84 + 90/10 is 37/4.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 10 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420
Likewise, for the 2nd fraction, since 10 × 42 = 420,
90/10 = 90 × 42/10 × 42 = 3780/420
Add the two like fractions:
105/420 + 3780/420 = 105 + 3780/420 = 3885/420
3885/420 simplified gives 37/4
So, 21/84 + 90/10 = 37/4
In mixed form: 91/4

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