Add 7/21 and 42/20, Solve 7/21 + 2 2/20 as a fraction

Add 7/21 and 42/20

1^st number: 7/21, 2^nd number: 2 2/20

7/21 + 42/20 is 73/30.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
42/20 = 42 × 21/20 × 21 = 882/420
Add the two like fractions:
140/420 + 882/420 = 140 + 882/420 = 1022/420
1022/420 simplified gives 73/30
So, 7/21 + 42/20 = 73/30
In mixed form: 213/30

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