Add 80/21 and 63/40, Solve 3 17/21 + 1 23/40 as a fraction

Add 80/21 and 63/40

1^st number: 3 17/21, 2^nd number: 1 23/40

80/21 + 63/40 is 4523/840.

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,
80/21 = 80 × 40/21 × 40 = 3200/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
63/40 = 63 × 21/40 × 21 = 1323/840
Add the two like fractions:
3200/840 + 1323/840 = 3200 + 1323/840 = 4523/840
So, 80/21 + 63/40 = 4523/840
In mixed form: 5323/840

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