Add 4/21 and 72/40, Solve 4/21 + 1 32/40 as a fraction

Add 4/21 and 72/40

1^st number: 4/21, 2^nd number: 1 32/40

4/21 + 72/40 is 209/105.

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,
72/40 = 72 × 21/40 × 21 = 1512/840
Add the two like fractions:
160/840 + 1512/840 = 160 + 1512/840 = 1672/840
1672/840 simplified gives 209/105
So, 4/21 + 72/40 = 209/105
In mixed form: 1104/105

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