Finding the Fourth Proportional to 10,985.43, 15,166.88 and 7,215.29

Step by Step Solution

1. Step 1: Write the proportion equation
   10,985.43 : 15,166.88 = 7,215.29 : x
2. Step 2: Convert to fraction form
   10,985.43/15,166.88 = 7,215.29/x
3. Step 3: Cross multiply
   10,985.43x = 15,166.88 × 7,215.29
4. Step 4: Simplify right side
   10,985.43x = 109,433,437.60
5. Step 5: Solve for x
   x = 109,433,437.60/10,985.43
6. Step 6: Final answer
   x = 9,961.69