Finding the Fourth Proportional to 1,386.14, 1,912.54 and 826.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.14 : 1,912.54 = 826.81 : x
2. Step 2: Convert to fraction form
   1,386.14/1,912.54 = 826.81/x
3. Step 3: Cross multiply
   1,386.14x = 1,912.54 × 826.81
4. Step 4: Simplify right side
   1,386.14x = 1,581,307.52
5. Step 5: Solve for x
   x = 1,581,307.52/1,386.14
6. Step 6: Final answer
   x = 1,140.80