Finding the Fourth Proportional to 1,385.99, 1,913.06 and 826.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.99 : 1,913.06 = 826.28 : x
2. Step 2: Convert to fraction form
   1,385.99/1,913.06 = 826.28/x
3. Step 3: Cross multiply
   1,385.99x = 1,913.06 × 826.28
4. Step 4: Simplify right side
   1,385.99x = 1,580,723.22
5. Step 5: Solve for x
   x = 1,580,723.22/1,385.99
6. Step 6: Final answer
   x = 1,140.50