Add 4/5 and 21/42, Solve 4/5 + 21/42 as a fraction

Add 4/5 and 21/42

4/5 + 21/42 is 13/10.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 5 × 42 = 210,
4/5 = 4 × 42/5 × 42 = 168/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
168/210 + 105/210 = 168 + 105/210 = 273/210
273/210 simplified gives 13/10
So, 4/5 + 21/42 = 13/10
In mixed form: 13/10

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