Add 84/4 and 21/70, Solve 21 0/4 + 21/70 as a fraction

Add 84/4 and 21/70

1^st number: 21 0/4, 2^nd number: 21/70

84/4 + 21/70 is 213/10.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 70 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 4 × 35 = 140,
84/4 = 84 × 35/4 × 35 = 2940/140
Likewise, for the 2nd fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140
Add the two like fractions:
2940/140 + 42/140 = 2940 + 42/140 = 2982/140
2982/140 simplified gives 213/10
So, 84/4 + 21/70 = 213/10
In mixed form: 213/10

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