Finding the Fourth Proportional to 9,406.53, 12,980.57 and 5,428.94

Step by Step Solution

1. Step 1: Write the proportion equation
   9,406.53 : 12,980.57 = 5,428.94 : x
2. Step 2: Convert to fraction form
   9,406.53/12,980.57 = 5,428.94/x
3. Step 3: Cross multiply
   9,406.53x = 12,980.57 × 5,428.94
4. Step 4: Simplify right side
   9,406.53x = 70,470,643.65
5. Step 5: Solve for x
   x = 70,470,643.65/9,406.53
6. Step 6: Final answer
   x = 7,491.67