Add 72/21 and 48/72, Solve 3 9/21 + 48/72 as a fraction

Add 72/21 and 48/72

1^st number: 3 9/21, 2^nd number: 48/72

72/21 + 48/72 is 86/21.

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,
72/21 = 72 × 24/21 × 24 = 1728/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
48/72 = 48 × 7/72 × 7 = 336/504
Add the two like fractions:
1728/504 + 336/504 = 1728 + 336/504 = 2064/504
2064/504 simplified gives 86/21
So, 72/21 + 48/72 = 86/21
In mixed form: 42/21

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