Add 72/90 and 21/42
72/90 + 21/42 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 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 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630 - Add the two like fractions:
504/630 + 315/630 = 504 + 315/630 = 819/630 - 819/630 simplified gives 13/10
- So, 72/90 + 21/42 = 13/10
In mixed form: 13/10
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