Add 63/42 and 9/40, Solve 1 21/42 + 9/40 as a fraction

Add 63/42 and 9/40

1^st number: 1 21/42, 2^nd number: 9/40

63/42 + 9/40 is 69/40.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
63/42 = 63 × 20/42 × 20 = 1260/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840
Add the two like fractions:
1260/840 + 189/840 = 1260 + 189/840 = 1449/840
1449/840 simplified gives 69/40
So, 63/42 + 9/40 = 69/40
In mixed form: 129/40

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