Add 21/27 and 30/40, Solve 21/27 + 30/40 as a fraction

Add 21/27 and 30/40

21/27 + 30/40 is 55/36.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 40 is 1080

Next, find the equivalent fraction of both fractional numbers with denominator 1080
For the 1st fraction, since 27 × 40 = 1080,
21/27 = 21 × 40/27 × 40 = 840/1080
Likewise, for the 2nd fraction, since 40 × 27 = 1080,
30/40 = 30 × 27/40 × 27 = 810/1080
Add the two like fractions:
840/1080 + 810/1080 = 840 + 810/1080 = 1650/1080
1650/1080 simplified gives 55/36
So, 21/27 + 30/40 = 55/36
In mixed form: 119/36

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