Finding the Fourth Proportional to 1,386.16, 1,912.69 and 826.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.16 : 1,912.69 = 826.62 : x
2. Step 2: Convert to fraction form
   1,386.16/1,912.69 = 826.62/x
3. Step 3: Cross multiply
   1,386.16x = 1,912.69 × 826.62
4. Step 4: Simplify right side
   1,386.16x = 1,581,067.81
5. Step 5: Solve for x
   x = 1,581,067.81/1,386.16
6. Step 6: Final answer
   x = 1,140.61