Finding the Fourth Proportional to 1,139.01, 1,571.45 and 928.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.01 : 1,571.45 = 928.82 : x
2. Step 2: Convert to fraction form
   1,139.01/1,571.45 = 928.82/x
3. Step 3: Cross multiply
   1,139.01x = 1,571.45 × 928.82
4. Step 4: Simplify right side
   1,139.01x = 1,459,596.49
5. Step 5: Solve for x
   x = 1,459,596.49/1,139.01
6. Step 6: Final answer
   x = 1,281.46