Finding the Fourth Proportional to 1,382.28, 1,906.58 and 939.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,382.28 : 1,906.58 = 939.42 : x
2. Step 2: Convert to fraction form
   1,382.28/1,906.58 = 939.42/x
3. Step 3: Cross multiply
   1,382.28x = 1,906.58 × 939.42
4. Step 4: Simplify right side
   1,382.28x = 1,791,079.38
5. Step 5: Solve for x
   x = 1,791,079.38/1,382.28
6. Step 6: Final answer
   x = 1,295.74