Finding the Fourth Proportional to 9,409.56, 12,985.42 and 5,218.12

Step by Step Solution

1. Step 1: Write the proportion equation
   9,409.56 : 12,985.42 = 5,218.12 : x
2. Step 2: Convert to fraction form
   9,409.56/12,985.42 = 5,218.12/x
3. Step 3: Cross multiply
   9,409.56x = 12,985.42 × 5,218.12
4. Step 4: Simplify right side
   9,409.56x = 67,759,479.81
5. Step 5: Solve for x
   x = 67,759,479.81/9,409.56
6. Step 6: Final answer
   x = 7,201.13