Add 90/72 and 21/7
1st number: 1 18/72, 2nd number: 3 0/7
90/72 + 21/7 is 17/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Likewise, for the 2nd fraction, since 7 × 72 = 504,
21/7 = 21 × 72/7 × 72 = 1512/504 - Add the two like fractions:
630/504 + 1512/504 = 630 + 1512/504 = 2142/504 - 2142/504 simplified gives 17/4
- So, 90/72 + 21/7 = 17/4
In mixed form: 41/4
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