Add 18/21 and 56/40, Solve 18/21 + 1 16/40 as a fraction

Add 18/21 and 56/40

1^st number: 18/21, 2^nd number: 1 16/40

18/21 + 56/40 is 79/35.

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,
18/21 = 18 × 40/21 × 40 = 720/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
56/40 = 56 × 21/40 × 21 = 1176/840
Add the two like fractions:
720/840 + 1176/840 = 720 + 1176/840 = 1896/840
1896/840 simplified gives 79/35
So, 18/21 + 56/40 = 79/35
In mixed form: 29/35

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