Add 28/40 and 72/90
28/40 + 72/90 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
28/40 = 28 × 9/40 × 9 = 252/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
72/90 = 72 × 4/90 × 4 = 288/360 - Add the two like fractions:
252/360 + 288/360 = 252 + 288/360 = 540/360 - 540/360 simplified gives 3/2
- So, 28/40 + 72/90 = 3/2
In mixed form: 11/2
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