Add 18/21 and 40/72
18/21 + 40/72 is 89/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
18/21 = 18 × 24/21 × 24 = 432/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Add the two like fractions:
432/504 + 280/504 = 432 + 280/504 = 712/504 - 712/504 simplified gives 89/63
- So, 18/21 + 40/72 = 89/63
In mixed form: 126/63
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