Add 18/5 and 21/42, Solve 3 3/5 + 21/42 as a fraction

Add 18/5 and 21/42

1^st number: 3 3/5, 2^nd number: 21/42

18/5 + 21/42 is 41/10.

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,
18/5 = 18 × 42/5 × 42 = 756/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
756/210 + 105/210 = 756 + 105/210 = 861/210
861/210 simplified gives 41/10
So, 18/5 + 21/42 = 41/10
In mixed form: 41/10

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