Add 20/21 and 42/10, Solve 20/21 + 4 2/10 as a fraction

Add 20/21 and 42/10

1^st number: 20/21, 2^nd number: 4 2/10

20/21 + 42/10 is 541/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
42/10 = 42 × 21/10 × 21 = 882/210
Add the two like fractions:
200/210 + 882/210 = 200 + 882/210 = 1082/210
1082/210 simplified gives 541/105
So, 20/21 + 42/10 = 541/105
In mixed form: 516/105

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