Add 21/30 and 42/70
21/30 + 42/70 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
42/70 = 42 × 3/70 × 3 = 126/210 - Add the two like fractions:
147/210 + 126/210 = 147 + 126/210 = 273/210 - 273/210 simplified gives 13/10
- So, 21/30 + 42/70 = 13/10
In mixed form: 13/10
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