Finding the Fourth Proportional to 103.22, 142.32 and 72.16

Step by Step Solution

1. Step 1: Write the proportion equation
   103.22 : 142.32 = 72.16 : x
2. Step 2: Convert to fraction form
   103.22/142.32 = 72.16/x
3. Step 3: Cross multiply
   103.22x = 142.32 × 72.16
4. Step 4: Simplify right side
   103.22x = 10,269.10
5. Step 5: Solve for x
   x = 10,269.10/103.22
6. Step 6: Final answer
   x = 99.49