Finding the Fourth Proportional to 72.89, 109.15 and 61.42

Step by Step Solution

1. Step 1: Write the proportion equation
   72.89 : 109.15 = 61.42 : x
2. Step 2: Convert to fraction form
   72.89/109.15 = 61.42/x
3. Step 3: Cross multiply
   72.89x = 109.15 × 61.42
4. Step 4: Simplify right side
   72.89x = 6,703.99
5. Step 5: Solve for x
   x = 6,703.99/72.89
6. Step 6: Final answer
   x = 91.97