Add 21/70 and 9/72
21/70 + 9/72 is 17/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
21/70 = 21 × 36/70 × 36 = 756/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
9/72 = 9 × 35/72 × 35 = 315/2520 - Add the two like fractions:
756/2520 + 315/2520 = 756 + 315/2520 = 1071/2520 - 1071/2520 simplified gives 17/40
- So, 21/70 + 9/72 = 17/40
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