Finding the Fourth Proportional to 90.72, 125.06 and 63.05

Step by Step Solution

1. Step 1: Write the proportion equation
   90.72 : 125.06 = 63.05 : x
2. Step 2: Convert to fraction form
   90.72/125.06 = 63.05/x
3. Step 3: Cross multiply
   90.72x = 125.06 × 63.05
4. Step 4: Simplify right side
   90.72x = 7,884.09
5. Step 5: Solve for x
   x = 7,884.09/90.72
6. Step 6: Final answer
   x = 86.91