Add 21/72 and 12/70
21/72 + 12/70 is 389/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
21/72 = 21 × 35/72 × 35 = 735/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
12/70 = 12 × 36/70 × 36 = 432/2520 - Add the two like fractions:
735/2520 + 432/2520 = 735 + 432/2520 = 1167/2520 - 1167/2520 simplified gives 389/840
- So, 21/72 + 12/70 = 389/840
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