Finding the Fourth Proportional to 91.92, 137.94 and 39.86

Step by Step Solution

1. Step 1: Write the proportion equation
   91.92 : 137.94 = 39.86 : x
2. Step 2: Convert to fraction form
   91.92/137.94 = 39.86/x
3. Step 3: Cross multiply
   91.92x = 137.94 × 39.86
4. Step 4: Simplify right side
   91.92x = 5,498.29
5. Step 5: Solve for x
   x = 5,498.29/91.92
6. Step 6: Final answer
   x = 59.82