Finding the Fourth Proportional to 1,436.44, 1,982.20 and 869.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,436.44 : 1,982.20 = 869.28 : x
2. Step 2: Convert to fraction form
   1,436.44/1,982.20 = 869.28/x
3. Step 3: Cross multiply
   1,436.44x = 1,982.20 × 869.28
4. Step 4: Simplify right side
   1,436.44x = 1,723,086.82
5. Step 5: Solve for x
   x = 1,723,086.82/1,436.44
6. Step 6: Final answer
   x = 1,199.55