Add 1/21 and 72/45, Solve 1/21 + 1 27/45 as a fraction

Add 1/21 and 72/45

1^st number: 1/21, 2^nd number: 1 27/45

1/21 + 72/45 is 173/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
1/21 = 1 × 15/21 × 15 = 15/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
72/45 = 72 × 7/45 × 7 = 504/315
Add the two like fractions:
15/315 + 504/315 = 15 + 504/315 = 519/315
519/315 simplified gives 173/105
So, 1/21 + 72/45 = 173/105
In mixed form: 168/105

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