Add 30/40 and 72/90
30/40 + 72/90 is 31/20.
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,
30/40 = 30 × 9/40 × 9 = 270/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
72/90 = 72 × 4/90 × 4 = 288/360 - Add the two like fractions:
270/360 + 288/360 = 270 + 288/360 = 558/360 - 558/360 simplified gives 31/20
- So, 30/40 + 72/90 = 31/20
In mixed form: 111/20
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