Finding the Fourth Proportional to 8,402.50, 12,618.15 and 7,964.74

Step by Step Solution

1. Step 1: Write the proportion equation
   8,402.50 : 12,618.15 = 7,964.74 : x
2. Step 2: Convert to fraction form
   8,402.50/12,618.15 = 7,964.74/x
3. Step 3: Cross multiply
   8,402.50x = 12,618.15 × 7,964.74
4. Step 4: Simplify right side
   8,402.50x = 100,500,284.03
5. Step 5: Solve for x
   x = 100,500,284.03/8,402.50
6. Step 6: Final answer
   x = 11,960.76