Finding the Fourth Proportional to 1,360.80, 1,872.72 and 1,313.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,360.80 : 1,872.72 = 1,313.28 : x
2. Step 2: Convert to fraction form
   1,360.80/1,872.72 = 1,313.28/x
3. Step 3: Cross multiply
   1,360.80x = 1,872.72 × 1,313.28
4. Step 4: Simplify right side
   1,360.80x = 2,459,405.72
5. Step 5: Solve for x
   x = 2,459,405.72/1,360.80
6. Step 6: Final answer
   x = 1,807.32