Add 10/42 and 90/21, Solve 10/42 + 4 6/21 as a fraction

Add 10/42 and 90/21

1^st number: 10/42, 2^nd number: 4 6/21

10/42 + 90/21 is 95/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
10/42 = 10 × 1/42 × 1 = 10/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42
Add the two like fractions:
10/42 + 180/42 = 10 + 180/42 = 190/42
190/42 simplified gives 95/21
So, 10/42 + 90/21 = 95/21
In mixed form: 411/21

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