Add 16/18 and 21/40
16/18 + 21/40 is 509/360.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
16/18 = 16 × 20/18 × 20 = 320/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
320/360 + 189/360 = 320 + 189/360 = 509/360 - So, 16/18 + 21/40 = 509/360
In mixed form: 1149/360
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