Add 28/40 and 30/90
28/40 + 30/90 is 31/30.
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,
30/90 = 30 × 4/90 × 4 = 120/360 - Add the two like fractions:
252/360 + 120/360 = 252 + 120/360 = 372/360 - 372/360 simplified gives 31/30
- So, 28/40 + 30/90 = 31/30
In mixed form: 11/30
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