Add 21/45 and 42/70
21/45 + 42/70 is 16/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
42/70 = 42 × 9/70 × 9 = 378/630 - Add the two like fractions:
294/630 + 378/630 = 294 + 378/630 = 672/630 - 672/630 simplified gives 16/15
- So, 21/45 + 42/70 = 16/15
In mixed form: 11/15
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