Finding the Fourth Proportional to 17,128.22, 25,689.98 and 5,120.20

Step by Step Solution

1. Step 1: Write the proportion equation
   17,128.22 : 25,689.98 = 5,120.20 : x
2. Step 2: Convert to fraction form
   17,128.22/25,689.98 = 5,120.20/x
3. Step 3: Cross multiply
   17,128.22x = 25,689.98 × 5,120.20
4. Step 4: Simplify right side
   17,128.22x = 131,537,835.60
5. Step 5: Solve for x
   x = 131,537,835.60/17,128.22
6. Step 6: Final answer
   x = 7,679.60