Finding the Fourth Proportional to 498.86, 747.60 and 389.31

Step by Step Solution

1. Step 1: Write the proportion equation
   498.86 : 747.60 = 389.31 : x
2. Step 2: Convert to fraction form
   498.86/747.60 = 389.31/x
3. Step 3: Cross multiply
   498.86x = 747.60 × 389.31
4. Step 4: Simplify right side
   498.86x = 291,048.16
5. Step 5: Solve for x
   x = 291,048.16/498.86
6. Step 6: Final answer
   x = 583.43