Finding the Fourth Proportional to 1,386.21, 1,913.21 and 826.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.21 : 1,913.21 = 826.71 : x
2. Step 2: Convert to fraction form
   1,386.21/1,913.21 = 826.71/x
3. Step 3: Cross multiply
   1,386.21x = 1,913.21 × 826.71
4. Step 4: Simplify right side
   1,386.21x = 1,581,665.71
5. Step 5: Solve for x
   x = 1,581,665.71/1,386.21
6. Step 6: Final answer
   x = 1,141.00