Finding the Fourth Proportional to 7,312.80, 10,080.72 and 5,320.20

Step by Step Solution

1. Step 1: Write the proportion equation
   7,312.80 : 10,080.72 = 5,320.20 : x
2. Step 2: Convert to fraction form
   7,312.80/10,080.72 = 5,320.20/x
3. Step 3: Cross multiply
   7,312.80x = 10,080.72 × 5,320.20
4. Step 4: Simplify right side
   7,312.80x = 53,631,446.54
5. Step 5: Solve for x
   x = 53,631,446.54/7,312.80
6. Step 6: Final answer
   x = 7,333.91