Add 42/70 and 20/90
42/70 + 20/90 is 37/45.
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,
20/90 = 20 × 7/90 × 7 = 140/630 - Add the two like fractions:
378/630 + 140/630 = 378 + 140/630 = 518/630 - 518/630 simplified gives 37/45
- So, 42/70 + 20/90 = 37/45
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