Add 80/21 and 7/40, Solve 3 17/21 + 7/40 as a fraction

Add 80/21 and 7/40

1^st number: 3 17/21, 2^nd number: 7/40

80/21 + 7/40 is 3347/840.

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,
7/40 = 7 × 21/40 × 21 = 147/840
Add the two like fractions:
3200/840 + 147/840 = 3200 + 147/840 = 3347/840
So, 80/21 + 7/40 = 3347/840
In mixed form: 3827/840

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