Finding the Fourth Proportional to 91.31, 136.92 and 39.94

Step by Step Solution

1. Step 1: Write the proportion equation
   91.31 : 136.92 = 39.94 : x
2. Step 2: Convert to fraction form
   91.31/136.92 = 39.94/x
3. Step 3: Cross multiply
   91.31x = 136.92 × 39.94
4. Step 4: Simplify right side
   91.31x = 5,468.83
5. Step 5: Solve for x
   x = 5,468.83/91.31
6. Step 6: Final answer
   x = 59.89