Answer: The empirical formula is 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of C= 68.75 g
Mass of H = 10.90 g
Mass of O = 20.35 g
Step 1 : convert given masses into moles.
Moles of C =
Moles of H =
Moles of O =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C = 
For H = 
For O =
The ratio of C : H: O= 4.5: 8.6: 1
converting them into whole number ratio by multiplying by 2

Hence the empirical formula is 