Add 80/90 and 15/40
80/90 + 15/40 is 91/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
80/90 = 80 × 4/90 × 4 = 320/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360 - Add the two like fractions:
320/360 + 135/360 = 320 + 135/360 = 455/360 - 455/360 simplified gives 91/72
- So, 80/90 + 15/40 = 91/72
In mixed form: 119/72
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