Add 72/45 and 21/42
1st number: 1 27/45, 2nd number: 21/42
72/45 + 21/42 is 21/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
72/45 = 72 × 14/45 × 14 = 1008/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630 - Add the two like fractions:
1008/630 + 315/630 = 1008 + 315/630 = 1323/630 - 1323/630 simplified gives 21/10
- So, 72/45 + 21/42 = 21/10
In mixed form: 21/10
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