Finding the Fourth Proportional to 105.91, 145.89 and 97.72

Step by Step Solution

1. Step 1: Write the proportion equation
   105.91 : 145.89 = 97.72 : x
2. Step 2: Convert to fraction form
   105.91/145.89 = 97.72/x
3. Step 3: Cross multiply
   105.91x = 145.89 × 97.72
4. Step 4: Simplify right side
   105.91x = 14,256.37
5. Step 5: Solve for x
   x = 14,256.37/105.91
6. Step 6: Final answer
   x = 134.61