Finding the Fourth Proportional to 1,147.78, 1,721.67 and 282.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,147.78 : 1,721.67 = 282.09 : x
2. Step 2: Convert to fraction form
   1,147.78/1,721.67 = 282.09/x
3. Step 3: Cross multiply
   1,147.78x = 1,721.67 × 282.09
4. Step 4: Simplify right side
   1,147.78x = 485,665.89
5. Step 5: Solve for x
   x = 485,665.89/1,147.78
6. Step 6: Final answer
   x = 423.14