Add 21/42 and 90/60, Solve 21/42 + 1 30/60 as a fraction

Add 21/42 and 90/60

1^st number: 21/42, 2^nd number: 1 30/60

21/42 + 90/60 is 2/1.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
90/60 = 90 × 7/60 × 7 = 630/420
Add the two like fractions:
210/420 + 630/420 = 210 + 630/420 = 840/420
840/420 simplified gives 2/1
So, 21/42 + 90/60 = 2/1

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