Finding the Fourth Proportional to 9,383.99, 12,920.40 and 7,964.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,383.99 : 12,920.40 = 7,964.72 : x
2. Step 2: Convert to fraction form
   9,383.99/12,920.40 = 7,964.72/x
3. Step 3: Cross multiply
   9,383.99x = 12,920.40 × 7,964.72
4. Step 4: Simplify right side
   9,383.99x = 102,907,368.29
5. Step 5: Solve for x
   x = 102,907,368.29/9,383.99
6. Step 6: Final answer
   x = 10,966.27