Finding the Fourth Proportional to 978.72, 1,350.38 and 585.47

Step by Step Solution

1. Step 1: Write the proportion equation
   978.72 : 1,350.38 = 585.47 : x
2. Step 2: Convert to fraction form
   978.72/1,350.38 = 585.47/x
3. Step 3: Cross multiply
   978.72x = 1,350.38 × 585.47
4. Step 4: Simplify right side
   978.72x = 790,601.69
5. Step 5: Solve for x
   x = 790,601.69/978.72
6. Step 6: Final answer
   x = 807.79