Add 21/70 and 45/30
1st number: 21/70, 2nd number: 1 15/30
21/70 + 45/30 is 9/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
45/30 = 45 × 7/30 × 7 = 315/210 - Add the two like fractions:
63/210 + 315/210 = 63 + 315/210 = 378/210 - 378/210 simplified gives 9/5
- So, 21/70 + 45/30 = 9/5
In mixed form: 14/5
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