Add 21/5 and 4/42, Solve 4 1/5 + 4/42 as a fraction

Add 21/5 and 4/42

1^st number: 4 1/5, 2^nd number: 4/42

21/5 + 4/42 is 451/105.

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,
21/5 = 21 × 42/5 × 42 = 882/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
4/42 = 4 × 5/42 × 5 = 20/210
Add the two like fractions:
882/210 + 20/210 = 882 + 20/210 = 902/210
902/210 simplified gives 451/105
So, 21/5 + 4/42 = 451/105
In mixed form: 431/105

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