Finding the Fourth Proportional to 72.39, 109.15 and 67.61

Step by Step Solution

1. Step 1: Write the proportion equation
   72.39 : 109.15 = 67.61 : x
2. Step 2: Convert to fraction form
   72.39/109.15 = 67.61/x
3. Step 3: Cross multiply
   72.39x = 109.15 × 67.61
4. Step 4: Simplify right side
   72.39x = 7,379.74
5. Step 5: Solve for x
   x = 7,379.74/72.39
6. Step 6: Final answer
   x = 101.94