Add 72/21 and 42/90
1st number: 3 9/21, 2nd number: 42/90
72/21 + 42/90 is 409/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
72/21 = 72 × 30/21 × 30 = 2160/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
2160/630 + 294/630 = 2160 + 294/630 = 2454/630 - 2454/630 simplified gives 409/105
- So, 72/21 + 42/90 = 409/105
In mixed form: 394/105
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