Add 20/72 and 42/45
20/72 + 42/45 is 109/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
42/45 = 42 × 8/45 × 8 = 336/360 - Add the two like fractions:
100/360 + 336/360 = 100 + 336/360 = 436/360 - 436/360 simplified gives 109/90
- So, 20/72 + 42/45 = 109/90
In mixed form: 119/90
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