Finding the Fourth Proportional to 7,485.95, 10,330.16 and 4,128.80

Step by Step Solution

1. Step 1: Write the proportion equation
   7,485.95 : 10,330.16 = 4,128.80 : x
2. Step 2: Convert to fraction form
   7,485.95/10,330.16 = 4,128.80/x
3. Step 3: Cross multiply
   7,485.95x = 10,330.16 × 4,128.80
4. Step 4: Simplify right side
   7,485.95x = 42,651,164.61
5. Step 5: Solve for x
   x = 42,651,164.61/7,485.95
6. Step 6: Final answer
   x = 5,697.50