Finding the Fourth Proportional to 105.35, 158.20 and 91.94

Step by Step Solution

1. Step 1: Write the proportion equation
   105.35 : 158.20 = 91.94 : x
2. Step 2: Convert to fraction form
   105.35/158.20 = 91.94/x
3. Step 3: Cross multiply
   105.35x = 158.20 × 91.94
4. Step 4: Simplify right side
   105.35x = 14,543.89
5. Step 5: Solve for x
   x = 14,543.89/105.35
6. Step 6: Final answer
   x = 138.06