Add 9/5 and 42/21, Solve 1 4/5 + 2 0/21 as a fraction

Add 9/5 and 42/21

1^st number: 1 4/5, 2^nd number: 2 0/21

9/5 + 42/21 is 19/5.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
9/5 = 9 × 21/5 × 21 = 189/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105
Add the two like fractions:
189/105 + 210/105 = 189 + 210/105 = 399/105
399/105 simplified gives 19/5
So, 9/5 + 42/21 = 19/5
In mixed form: 34/5

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