Finding the Fourth Proportional to 1,005.48, 1,387.98 and 657.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.48 : 1,387.98 = 657.18 : x
2. Step 2: Convert to fraction form
   1,005.48/1,387.98 = 657.18/x
3. Step 3: Cross multiply
   1,005.48x = 1,387.98 × 657.18
4. Step 4: Simplify right side
   1,005.48x = 912,152.70
5. Step 5: Solve for x
   x = 912,152.70/1,005.48
6. Step 6: Final answer
   x = 907.18