Add 21/84 and 42/45
21/84 + 42/45 is 71/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
42/45 = 42 × 28/45 × 28 = 1176/1260 - Add the two like fractions:
315/1260 + 1176/1260 = 315 + 1176/1260 = 1491/1260 - 1491/1260 simplified gives 71/60
- So, 21/84 + 42/45 = 71/60
In mixed form: 111/60
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