Finding the Fourth Proportional to 9,361.31, 12,918.60 and 5,383.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,361.31 : 12,918.60 = 5,383.20 : x
2. Step 2: Convert to fraction form
   9,361.31/12,918.60 = 5,383.20/x
3. Step 3: Cross multiply
   9,361.31x = 12,918.60 × 5,383.20
4. Step 4: Simplify right side
   9,361.31x = 69,543,407.52
5. Step 5: Solve for x
   x = 69,543,407.52/9,361.31
6. Step 6: Final answer
   x = 7,428.81