Add 84/42 and 4/40, Solve 2 0/42 + 4/40 as a fraction

Add 84/42 and 4/40

1^st number: 2 0/42, 2^nd number: 4/40

84/42 + 4/40 is 21/10.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
84/42 = 84 × 20/42 × 20 = 1680/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840
Add the two like fractions:
1680/840 + 84/840 = 1680 + 84/840 = 1764/840
1764/840 simplified gives 21/10
So, 84/42 + 4/40 = 21/10
In mixed form: 21/10

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