Add 21/18 and 72/40
1st number: 1 3/18, 2nd number: 1 32/40
21/18 + 72/40 is 89/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
21/18 = 21 × 20/18 × 20 = 420/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
72/40 = 72 × 9/40 × 9 = 648/360 - Add the two like fractions:
420/360 + 648/360 = 420 + 648/360 = 1068/360 - 1068/360 simplified gives 89/30
- So, 21/18 + 72/40 = 89/30
In mixed form: 229/30
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