Add 9/10 and 63/42, Solve 9/10 + 1 21/42 as a fraction

Add 9/10 and 63/42

1^st number: 9/10, 2^nd number: 1 21/42

9/10 + 63/42 is 12/5.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210
Add the two like fractions:
189/210 + 315/210 = 189 + 315/210 = 504/210
504/210 simplified gives 12/5
So, 9/10 + 63/42 = 12/5
In mixed form: 22/5

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