Finding the Fourth Proportional to 1,009.48, 1,392.54 and 636.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,009.48 : 1,392.54 = 636.32 : x
2. Step 2: Convert to fraction form
   1,009.48/1,392.54 = 636.32/x
3. Step 3: Cross multiply
   1,009.48x = 1,392.54 × 636.32
4. Step 4: Simplify right side
   1,009.48x = 886,099.85
5. Step 5: Solve for x
   x = 886,099.85/1,009.48
6. Step 6: Final answer
   x = 877.78