Add 21/5 and 20/72
1st number: 4 1/5, 2nd number: 20/72
21/5 + 20/72 is 403/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 5 × 72 = 360,
21/5 = 21 × 72/5 × 72 = 1512/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Add the two like fractions:
1512/360 + 100/360 = 1512 + 100/360 = 1612/360 - 1612/360 simplified gives 403/90
- So, 21/5 + 20/72 = 403/90
In mixed form: 443/90
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