Add 90/70 and 18/72
1st number: 1 20/70, 2nd number: 18/72
90/70 + 18/72 is 43/28.
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,
90/70 = 90 × 36/70 × 36 = 3240/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
18/72 = 18 × 35/72 × 35 = 630/2520 - Add the two like fractions:
3240/2520 + 630/2520 = 3240 + 630/2520 = 3870/2520 - 3870/2520 simplified gives 43/28
- So, 90/70 + 18/72 = 43/28
In mixed form: 115/28
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