Finding the Fourth Proportional to 1,003.37, 1,505.86 and 426.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.37 : 1,505.86 = 426.65 : x
2. Step 2: Convert to fraction form
   1,003.37/1,505.86 = 426.65/x
3. Step 3: Cross multiply
   1,003.37x = 1,505.86 × 426.65
4. Step 4: Simplify right side
   1,003.37x = 642,466.57
5. Step 5: Solve for x
   x = 642,466.57/1,003.37
6. Step 6: Final answer
   x = 640.31