Add 18/42 and 21/5, Solve 18/42 + 4 1/5 as a fraction

Add 18/42 and 21/5

1^st number: 18/42, 2^nd number: 4 1/5

18/42 + 21/5 is 162/35.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
21/5 = 21 × 42/5 × 42 = 882/210
Add the two like fractions:
90/210 + 882/210 = 90 + 882/210 = 972/210
972/210 simplified gives 162/35
So, 18/42 + 21/5 = 162/35
In mixed form: 422/35

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