Finding the Fourth Proportional to 1,078.56, 1,488.48 and 612.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.56 : 1,488.48 = 612.84 : x
2. Step 2: Convert to fraction form
   1,078.56/1,488.48 = 612.84/x
3. Step 3: Cross multiply
   1,078.56x = 1,488.48 × 612.84
4. Step 4: Simplify right side
   1,078.56x = 912,200.08
5. Step 5: Solve for x
   x = 912,200.08/1,078.56
6. Step 6: Final answer
   x = 845.76