Finding the Fourth Proportional to 103.63, 142.76 and 72.50

Step by Step Solution

1. Step 1: Write the proportion equation
   103.63 : 142.76 = 72.50 : x
2. Step 2: Convert to fraction form
   103.63/142.76 = 72.50/x
3. Step 3: Cross multiply
   103.63x = 142.76 × 72.50
4. Step 4: Simplify right side
   103.63x = 10,349.57
5. Step 5: Solve for x
   x = 10,349.57/103.63
6. Step 6: Final answer
   x = 99.87