Finding the Fourth Proportional to 1,007.69, 1,391.00 and 902.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.69 : 1,391.00 = 902.61 : x
2. Step 2: Convert to fraction form
   1,007.69/1,391.00 = 902.61/x
3. Step 3: Cross multiply
   1,007.69x = 1,391.00 × 902.61
4. Step 4: Simplify right side
   1,007.69x = 1,255,526.00
5. Step 5: Solve for x
   x = 1,255,526.00/1,007.69
6. Step 6: Final answer
   x = 1,245.95