Add 64/21 and 49/40, Solve 3 1/21 + 1 9/40 as a fraction

Add 64/21 and 49/40

1^st number: 3 1/21, 2^nd number: 1 9/40

64/21 + 49/40 is 3589/840.

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

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
64/21 = 64 × 40/21 × 40 = 2560/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
49/40 = 49 × 21/40 × 21 = 1029/840
Add the two like fractions:
2560/840 + 1029/840 = 2560 + 1029/840 = 3589/840
So, 64/21 + 49/40 = 3589/840
In mixed form: 4229/840

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