Add 54/21 and 90/72, Solve 2 12/21 + 1 18/72 as a fraction

Add 54/21 and 90/72

1^st number: 2 12/21, 2^nd number: 1 18/72

54/21 + 90/72 is 107/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
54/21 = 54 × 24/21 × 24 = 1296/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504
Add the two like fractions:
1296/504 + 630/504 = 1296 + 630/504 = 1926/504
1926/504 simplified gives 107/28
So, 54/21 + 90/72 = 107/28
In mixed form: 323/28

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