Finding the Fourth Proportional to 103.69, 143.01 and 72.55

Step by Step Solution

1. Step 1: Write the proportion equation
   103.69 : 143.01 = 72.55 : x
2. Step 2: Convert to fraction form
   103.69/143.01 = 72.55/x
3. Step 3: Cross multiply
   103.69x = 143.01 × 72.55
4. Step 4: Simplify right side
   103.69x = 10,375.38
5. Step 5: Solve for x
   x = 10,375.38/103.69
6. Step 6: Final answer
   x = 100.06