Finding the Fourth Proportional to 1,382.31, 2,069.96 and 918.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,382.31 : 2,069.96 = 918.72 : x
2. Step 2: Convert to fraction form
   1,382.31/2,069.96 = 918.72/x
3. Step 3: Cross multiply
   1,382.31x = 2,069.96 × 918.72
4. Step 4: Simplify right side
   1,382.31x = 1,901,709.06
5. Step 5: Solve for x
   x = 1,901,709.06/1,382.31
6. Step 6: Final answer
   x = 1,375.75