Add 42/70 and 72/90
42/70 + 72/90 is 7/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
42/70 = 42 × 9/70 × 9 = 378/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Add the two like fractions:
378/630 + 504/630 = 378 + 504/630 = 882/630 - 882/630 simplified gives 7/5
- So, 42/70 + 72/90 = 7/5
In mixed form: 12/5
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