Finding the Fourth Proportional to 30,559.55, 42,172.12 and 17,130.80

Step by Step Solution

1. Step 1: Write the proportion equation
   30,559.55 : 42,172.12 = 17,130.80 : x
2. Step 2: Convert to fraction form
   30,559.55/42,172.12 = 17,130.80/x
3. Step 3: Cross multiply
   30,559.55x = 42,172.12 × 17,130.80
4. Step 4: Simplify right side
   30,559.55x = 722,441,899.61
5. Step 5: Solve for x
   x = 722,441,899.61/30,559.55
6. Step 6: Final answer
   x = 23,640.47