Finding the Fourth Proportional to 100.06, 138.02 and 72.50

Step by Step Solution

1. Step 1: Write the proportion equation
   100.06 : 138.02 = 72.50 : x
2. Step 2: Convert to fraction form
   100.06/138.02 = 72.50/x
3. Step 3: Cross multiply
   100.06x = 138.02 × 72.50
4. Step 4: Simplify right side
   100.06x = 10,006.45
5. Step 5: Solve for x
   x = 10,006.45/100.06
6. Step 6: Final answer
   x = 100.00