To divide the gym value of 80 into 10 pieces of equal value, each piece should be worth 8 (since 80 รท 10 = 8).
Now, let's calculate the values of the options given as percentages of the total value (80):
- 50% of 80 = 40
- 20% of 80 = 16
- 10% of 80 = 8
- 25% of 80 = 20
From the options, 10% of 80 equals 8, which correctly breaks the gym into 10 pieces (since each piece will be worth 8).
So, the answer is 10%.