Add 81/72 and 42/70
1st number: 1 9/72, 2nd number: 42/70
81/72 + 42/70 is 69/40.
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,
81/72 = 81 × 35/72 × 35 = 2835/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
42/70 = 42 × 36/70 × 36 = 1512/2520 - Add the two like fractions:
2835/2520 + 1512/2520 = 2835 + 1512/2520 = 4347/2520 - 4347/2520 simplified gives 69/40
- So, 81/72 + 42/70 = 69/40
In mixed form: 129/40
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