Finding the Fourth Proportional to 103.24, 142.42 and 72.19

Step by Step Solution

1. Step 1: Write the proportion equation
   103.24 : 142.42 = 72.19 : x
2. Step 2: Convert to fraction form
   103.24/142.42 = 72.19/x
3. Step 3: Cross multiply
   103.24x = 142.42 × 72.19
4. Step 4: Simplify right side
   103.24x = 10,280.59
5. Step 5: Solve for x
   x = 10,280.59/103.24
6. Step 6: Final answer
   x = 99.58