Add 45/72 and 40/21
1st number: 45/72, 2nd number: 1 19/21
45/72 + 40/21 is 425/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
40/21 = 40 × 24/21 × 24 = 960/504 - Add the two like fractions:
315/504 + 960/504 = 315 + 960/504 = 1275/504 - 1275/504 simplified gives 425/168
- So, 45/72 + 40/21 = 425/168
In mixed form: 289/168
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