Finding the Fourth Proportional to 13,167.50, 18,171.16 and 7,578.50

Step by Step Solution

1. Step 1: Write the proportion equation
   13,167.50 : 18,171.16 = 7,578.50 : x
2. Step 2: Convert to fraction form
   13,167.50/18,171.16 = 7,578.50/x
3. Step 3: Cross multiply
   13,167.50x = 18,171.16 × 7,578.50
4. Step 4: Simplify right side
   13,167.50x = 137,710,136.06
5. Step 5: Solve for x
   x = 137,710,136.06/13,167.50
6. Step 6: Final answer
   x = 10,458.34