Finding the Fourth Proportional to 91.10, 136.55 and 39.69

Step by Step Solution

1. Step 1: Write the proportion equation
   91.10 : 136.55 = 39.69 : x
2. Step 2: Convert to fraction form
   91.10/136.55 = 39.69/x
3. Step 3: Cross multiply
   91.10x = 136.55 × 39.69
4. Step 4: Simplify right side
   91.10x = 5,419.47
5. Step 5: Solve for x
   x = 5,419.47/91.10
6. Step 6: Final answer
   x = 59.49