Add 21/42 and 90/5, Solve 21/42 + 18 0/5 as a fraction

Add 21/42 and 90/5

1^st number: 21/42, 2^nd number: 18 0/5

21/42 + 90/5 is 37/2.

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,
21/42 = 21 × 5/42 × 5 = 105/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
90/5 = 90 × 42/5 × 42 = 3780/210
Add the two like fractions:
105/210 + 3780/210 = 105 + 3780/210 = 3885/210
3885/210 simplified gives 37/2
So, 21/42 + 90/5 = 37/2
In mixed form: 181/2

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