Add 54/72 and 21/40
54/72 + 21/40 is 51/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
54/72 = 54 × 5/72 × 5 = 270/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
270/360 + 189/360 = 270 + 189/360 = 459/360 - 459/360 simplified gives 51/40
- So, 54/72 + 21/40 = 51/40
In mixed form: 111/40
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