Answer: E) 1/5
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Method 1
Use your calculator to find the decimal version of each fraction
- 4/10 = 0.40
- 12/25 = 0.48
- 14/20 = 0.70
- 28/50 = 0.56
- 1/5 = 0.20
We see that 0.20 is the smallest decimal of the list, so 1/5 is the smallest fraction of the list.
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Method 2
To compare fractions, we need to get all of the denominators to the same value. A good target is the lowest common denominator (LCD)
In this case, the LCD is 100
- 4/10 = 40/100 .... multiply top and bottom by 10
- 12/25 = 48/100 .... multiply top and bottom by 4
- 14/20 = 70/100 .... multiply top and bottom by 5
- 28/50 = 56/100 .... multiply top and bottom by 2
- 1/5 = 20/100 .... multiply top and bottom by 20
The last fraction has the smallest denominator, so 1/5 is the smallest.