Add 21/70 and 15/30
21/70 + 15/30 is 4/5.
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,
15/30 = 15 × 7/30 × 7 = 105/210 - Add the two like fractions:
63/210 + 105/210 = 63 + 105/210 = 168/210 - 168/210 simplified gives 4/5
- So, 21/70 + 15/30 = 4/5
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