Finding the Fourth Proportional to 162.24, 222.72 and 139.20

Step by Step Solution

1. Step 1: Write the proportion equation
   162.24 : 222.72 = 139.20 : x
2. Step 2: Convert to fraction form
   162.24/222.72 = 139.20/x
3. Step 3: Cross multiply
   162.24x = 222.72 × 139.20
4. Step 4: Simplify right side
   162.24x = 31,002.62
5. Step 5: Solve for x
   x = 31,002.62/162.24
6. Step 6: Final answer
   x = 191.09