Finding the Fourth Proportional to 72.86, 109.94 and 72.05

Step by Step Solution

1. Step 1: Write the proportion equation
   72.86 : 109.94 = 72.05 : x
2. Step 2: Convert to fraction form
   72.86/109.94 = 72.05/x
3. Step 3: Cross multiply
   72.86x = 109.94 × 72.05
4. Step 4: Simplify right side
   72.86x = 7,920.27
5. Step 5: Solve for x
   x = 7,920.27/72.86
6. Step 6: Final answer
   x = 108.71