Finding the Fourth Proportional to 1,599.10, 2,399.25 and 777.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,599.10 : 2,399.25 = 777.31 : x
2. Step 2: Convert to fraction form
   1,599.10/2,399.25 = 777.31/x
3. Step 3: Cross multiply
   1,599.10x = 2,399.25 × 777.31
4. Step 4: Simplify right side
   1,599.10x = 1,864,961.02
5. Step 5: Solve for x
   x = 1,864,961.02/1,599.10
6. Step 6: Final answer
   x = 1,166.26