Finding the Fourth Proportional to 30,559.91, 42,170.90 and 17,128.69

Step by Step Solution

1. Step 1: Write the proportion equation
   30,559.91 : 42,170.90 = 17,128.69 : x
2. Step 2: Convert to fraction form
   30,559.91/42,170.90 = 17,128.69/x
3. Step 3: Cross multiply
   30,559.91x = 42,170.90 × 17,128.69
4. Step 4: Simplify right side
   30,559.91x = 722,332,082.05
5. Step 5: Solve for x
   x = 722,332,082.05/30,559.91
6. Step 6: Final answer
   x = 23,636.59