Add 18/60 and 40/21, Solve 18/60 + 1 19/21 as a fraction

Add 18/60 and 40/21

1^st number: 18/60, 2^nd number: 1 19/21

18/60 + 40/21 is 463/210.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
18/60 = 18 × 7/60 × 7 = 126/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
40/21 = 40 × 20/21 × 20 = 800/420
Add the two like fractions:
126/420 + 800/420 = 126 + 800/420 = 926/420
926/420 simplified gives 463/210
So, 18/60 + 40/21 = 463/210
In mixed form: 243/210

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