Add 40/21 and 7/80, Solve 1 19/21 + 7/80 as a fraction

Add 40/21 and 7/80

1^st number: 1 19/21, 2^nd number: 7/80

40/21 + 7/80 is 3347/1680.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
40/21 = 40 × 80/21 × 80 = 3200/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
7/80 = 7 × 21/80 × 21 = 147/1680
Add the two like fractions:
3200/1680 + 147/1680 = 3200 + 147/1680 = 3347/1680
So, 40/21 + 7/80 = 3347/1680
In mixed form: 11667/1680

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