Finding the Fourth Proportional to 1,018.47, 1,404.75 and 663.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.47 : 1,404.75 = 663.75 : x
2. Step 2: Convert to fraction form
   1,018.47/1,404.75 = 663.75/x
3. Step 3: Cross multiply
   1,018.47x = 1,404.75 × 663.75
4. Step 4: Simplify right side
   1,018.47x = 932,402.81
5. Step 5: Solve for x
   x = 932,402.81/1,018.47
6. Step 6: Final answer
   x = 915.49