Add 72/42 and 21/90
1st number: 1 30/42, 2nd number: 21/90
72/42 + 21/90 is 409/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
72/42 = 72 × 15/42 × 15 = 1080/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
1080/630 + 147/630 = 1080 + 147/630 = 1227/630 - 1227/630 simplified gives 409/210
- So, 72/42 + 21/90 = 409/210
In mixed form: 1199/210
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