Add 15/42 and 90/72
1st number: 15/42, 2nd number: 1 18/72
15/42 + 90/72 is 45/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
15/42 = 15 × 12/42 × 12 = 180/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Add the two like fractions:
180/504 + 630/504 = 180 + 630/504 = 810/504 - 810/504 simplified gives 45/28
- So, 15/42 + 90/72 = 45/28
In mixed form: 117/28
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