Add 21/4 and 72/45
1st number: 5 1/4, 2nd number: 1 27/45
21/4 + 72/45 is 137/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 4 × 45 = 180,
21/4 = 21 × 45/4 × 45 = 945/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
72/45 = 72 × 4/45 × 4 = 288/180 - Add the two like fractions:
945/180 + 288/180 = 945 + 288/180 = 1233/180 - 1233/180 simplified gives 137/20
- So, 21/4 + 72/45 = 137/20
In mixed form: 617/20
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