Add 45/72 and 40/20
1st number: 45/72, 2nd number: 2 0/20
45/72 + 40/20 is 21/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
45/72 = 45 × 5/72 × 5 = 225/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
40/20 = 40 × 18/20 × 18 = 720/360 - Add the two like fractions:
225/360 + 720/360 = 225 + 720/360 = 945/360 - 945/360 simplified gives 21/8
- So, 45/72 + 40/20 = 21/8
In mixed form: 25/8
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