Finding the Fourth Proportional to 1,003.31, 1,384.58 and 561.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.31 : 1,384.58 = 561.23 : x
2. Step 2: Convert to fraction form
   1,003.31/1,384.58 = 561.23/x
3. Step 3: Cross multiply
   1,003.31x = 1,384.58 × 561.23
4. Step 4: Simplify right side
   1,003.31x = 777,067.83
5. Step 5: Solve for x
   x = 777,067.83/1,003.31
6. Step 6: Final answer
   x = 774.50