Add 4/21 and 81/40, Solve 4/21 + 2 1/40 as a fraction

Add 4/21 and 81/40

1^st number: 4/21, 2^nd number: 2 1/40

4/21 + 81/40 is 1861/840.

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,
4/21 = 4 × 40/21 × 40 = 160/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840
Add the two like fractions:
160/840 + 1701/840 = 160 + 1701/840 = 1861/840
So, 4/21 + 81/40 = 1861/840
In mixed form: 2181/840

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