Finding the Fourth Proportional to 143.30, 213.82 and 140.42

Step by Step Solution

1. Step 1: Write the proportion equation
   143.30 : 213.82 = 140.42 : x
2. Step 2: Convert to fraction form
   143.30/213.82 = 140.42/x
3. Step 3: Cross multiply
   143.30x = 213.82 × 140.42
4. Step 4: Simplify right side
   143.30x = 30,024.60
5. Step 5: Solve for x
   x = 30,024.60/143.30
6. Step 6: Final answer
   x = 209.52