Add 40/60 and 75/21, Solve 40/60 + 3 12/21 as a fraction

Add 40/60 and 75/21

1^st number: 40/60, 2^nd number: 3 12/21

40/60 + 75/21 is 89/21.

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,
40/60 = 40 × 7/60 × 7 = 280/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
75/21 = 75 × 20/21 × 20 = 1500/420
Add the two like fractions:
280/420 + 1500/420 = 280 + 1500/420 = 1780/420
1780/420 simplified gives 89/21
So, 40/60 + 75/21 = 89/21
In mixed form: 45/21

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