Add 72/90 and 9/42
72/90 + 9/42 is 71/70.
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,
9/42 = 9 × 15/42 × 15 = 135/630 - Add the two like fractions:
504/630 + 135/630 = 504 + 135/630 = 639/630 - 639/630 simplified gives 71/70
- So, 72/90 + 9/42 = 71/70
In mixed form: 11/70
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