Add 42/72 and 21/40
42/72 + 21/40 is 133/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
210/360 + 189/360 = 210 + 189/360 = 399/360 - 399/360 simplified gives 133/120
- So, 42/72 + 21/40 = 133/120
In mixed form: 113/120
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