Add 27/72 and 28/21, Solve 27/72 + 1 7/21 as a fraction

Add 27/72 and 28/21

1^st number: 27/72, 2^nd number: 1 7/21

27/72 + 28/21 is 41/24.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
27/72 = 27 × 7/72 × 7 = 189/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
28/21 = 28 × 24/21 × 24 = 672/504
Add the two like fractions:
189/504 + 672/504 = 189 + 672/504 = 861/504
861/504 simplified gives 41/24
So, 27/72 + 28/21 = 41/24
In mixed form: 117/24

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