Finding the Fourth Proportional to 9,405.82, 12,981.50 and 5,428.18

Step by Step Solution

1. Step 1: Write the proportion equation
   9,405.82 : 12,981.50 = 5,428.18 : x
2. Step 2: Convert to fraction form
   9,405.82/12,981.50 = 5,428.18/x
3. Step 3: Cross multiply
   9,405.82x = 12,981.50 × 5,428.18
4. Step 4: Simplify right side
   9,405.82x = 70,465,918.67
5. Step 5: Solve for x
   x = 70,465,918.67/9,405.82
6. Step 6: Final answer
   x = 7,491.74