Finding the Fourth Proportional to 9,404.28, 12,978 and 5,212.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,404.28 : 12,978 = 5,212.50 : x
2. Step 2: Convert to fraction form
   9,404.28/12,978 = 5,212.50/x
3. Step 3: Cross multiply
   9,404.28x = 12,978 × 5,212.50
4. Step 4: Simplify right side
   9,404.28x = 67,647,825
5. Step 5: Solve for x
   x = 67,647,825/9,404.28
6. Step 6: Final answer
   x = 7,193.30