Finding the Third Proportional to 142.17 and 384.54

Step by Step Solution

1. Step 1: Write the proportion equation
   142.17 : 384.54 = 384.54 : x
2. Step 2: Convert to fraction form
   142.17/384.54 = 384.54/x
3. Step 3: Cross multiply
   142.17x = 384.54 × 384.54
4. Step 4: Simplify right side
   142.17x = 147,870.29
5. Step 5: Solve for x
   x = 147,870.29/142.17
6. Step 6: Final answer
   x = 1,040.08