Finding the Fourth Proportional to 90.05, 124.38 and 72.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90.05 : 124.38 = 72.50 : x
2. Step 2: Convert to fraction form
   90.05/124.38 = 72.50/x
3. Step 3: Cross multiply
   90.05x = 124.38 × 72.50
4. Step 4: Simplify right side
   90.05x = 9,016.93
5. Step 5: Solve for x
   x = 9,016.93/90.05
6. Step 6: Final answer
   x = 100.14