Add 18/40 and 63/21, Solve 18/40 + 3 0/21 as a fraction

Add 18/40 and 63/21

1^st number: 18/40, 2^nd number: 3 0/21

18/40 + 63/21 is 69/20.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
63/21 = 63 × 40/21 × 40 = 2520/840
Add the two like fractions:
378/840 + 2520/840 = 378 + 2520/840 = 2898/840
2898/840 simplified gives 69/20
So, 18/40 + 63/21 = 69/20
In mixed form: 39/20

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