Answer: 7/8
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Step-by-step explanation
Use long division or a calculator to get the decimal form of each fraction.
- 7/8 = 0.875
- 3/8 = 0.375
- 2/5 = 0.400
- 1/4 = 0.250
Each value is exact. I extended things to 3 decimal places to make comparison fairly quick.
The largest decimal value mentioned is 0.875, so that makes 7/8 the largest fraction.
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Another approach
The LCM of 8, 5 and 4 is 40. This is the LCD of the fractions.
Rewrite each fraction in terms of the LCD
- 7/8 = (7/8)*(5/5) = 35/40
- 3/8 = (3/8)*(5/5) = 15/40
- 2/5 = (2/5)*(8/8) = 16/40
- 1/4 = (1/4)*(10/10) = 10/40
The largest fraction is 35/40 since it has the largest numerator. This leads us back to 7/8 being the final answer.