Finding the Fourth Proportional to 5,280.72, 7,287.60 and 2,923.20

Step by Step Solution

1. Step 1: Write the proportion equation
   5,280.72 : 7,287.60 = 2,923.20 : x
2. Step 2: Convert to fraction form
   5,280.72/7,287.60 = 2,923.20/x
3. Step 3: Cross multiply
   5,280.72x = 7,287.60 × 2,923.20
4. Step 4: Simplify right side
   5,280.72x = 21,303,112.32
5. Step 5: Solve for x
   x = 21,303,112.32/5,280.72
6. Step 6: Final answer
   x = 4,034.13