Subtract 30/84 from 42/45
42/45 - 30/84 is 121/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 45 × 28 = 1260,
42/45 = 42 × 28/45 × 28 = 1176/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
30/84 = 30 × 15/84 × 15 = 450/1260 - Subtract the two like fractions:
1176/1260 - 450/1260 = 1176 - 450/1260 = 726/1260 - After reducing the fraction, the answer is 121/210
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