Add 72/45 and 21/40
1st number: 1 27/45, 2nd number: 21/40
72/45 + 21/40 is 17/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
72/45 = 72 × 8/45 × 8 = 576/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
576/360 + 189/360 = 576 + 189/360 = 765/360 - 765/360 simplified gives 17/8
- So, 72/45 + 21/40 = 17/8
In mixed form: 21/8
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