Finding the Fourth Proportional to 1,078.50, 1,488.42 and 612.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.50 : 1,488.42 = 612.84 : x
2. Step 2: Convert to fraction form
   1,078.50/1,488.42 = 612.84/x
3. Step 3: Cross multiply
   1,078.50x = 1,488.42 × 612.84
4. Step 4: Simplify right side
   1,078.50x = 912,163.31
5. Step 5: Solve for x
   x = 912,163.31/1,078.50
6. Step 6: Final answer
   x = 845.77