Add 21/42 and 9/5, Solve 21/42 + 1 4/5 as a fraction

Add 21/42 and 9/5

1^st number: 21/42, 2^nd number: 1 4/5

21/42 + 9/5 is 23/10.

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,
9/5 = 9 × 42/5 × 42 = 378/210
Add the two like fractions:
105/210 + 378/210 = 105 + 378/210 = 483/210
483/210 simplified gives 23/10
So, 21/42 + 9/5 = 23/10
In mixed form: 23/10

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