Add 72/90 and 21/70
72/90 + 21/70 is 11/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Add the two like fractions:
504/630 + 189/630 = 504 + 189/630 = 693/630 - 693/630 simplified gives 11/10
- So, 72/90 + 21/70 = 11/10
In mixed form: 11/10
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