Add 10/21 and 80/40, Solve 10/21 + 2 0/40 as a fraction

Add 10/21 and 80/40

1^st number: 10/21, 2^nd number: 2 0/40

10/21 + 80/40 is 52/21.

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,
10/21 = 10 × 40/21 × 40 = 400/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
80/40 = 80 × 21/40 × 21 = 1680/840
Add the two like fractions:
400/840 + 1680/840 = 400 + 1680/840 = 2080/840
2080/840 simplified gives 52/21
So, 10/21 + 80/40 = 52/21
In mixed form: 210/21

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