Finding the Fourth Proportional to 1,025.06, 1,539.41 and 978.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,025.06 : 1,539.41 = 978.89 : x
2. Step 2: Convert to fraction form
   1,025.06/1,539.41 = 978.89/x
3. Step 3: Cross multiply
   1,025.06x = 1,539.41 × 978.89
4. Step 4: Simplify right side
   1,025.06x = 1,506,900.46
5. Step 5: Solve for x
   x = 1,506,900.46/1,025.06
6. Step 6: Final answer
   x = 1,470.07