Finding the Fourth Proportional to 1,433.79, 1,978.52 and 909.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,433.79 : 1,978.52 = 909.63 : x
2. Step 2: Convert to fraction form
   1,433.79/1,978.52 = 909.63/x
3. Step 3: Cross multiply
   1,433.79x = 1,978.52 × 909.63
4. Step 4: Simplify right side
   1,433.79x = 1,799,716.60
5. Step 5: Solve for x
   x = 1,799,716.60/1,433.79
6. Step 6: Final answer
   x = 1,255.22