Finding the Fourth Proportional to 9,357.99, 12,913.58 and 5,109.21

Step by Step Solution

1. Step 1: Write the proportion equation
   9,357.99 : 12,913.58 = 5,109.21 : x
2. Step 2: Convert to fraction form
   9,357.99/12,913.58 = 5,109.21/x
3. Step 3: Cross multiply
   9,357.99x = 12,913.58 × 5,109.21
4. Step 4: Simplify right side
   9,357.99x = 65,978,166.53
5. Step 5: Solve for x
   x = 65,978,166.53/9,357.99
6. Step 6: Final answer
   x = 7,050.46