Finding the Fourth Proportional to 1,383.18, 1,908.42 and 989.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.18 : 1,908.42 = 989.52 : x
2. Step 2: Convert to fraction form
   1,383.18/1,908.42 = 989.52/x
3. Step 3: Cross multiply
   1,383.18x = 1,908.42 × 989.52
4. Step 4: Simplify right side
   1,383.18x = 1,888,419.76
5. Step 5: Solve for x
   x = 1,888,419.76/1,383.18
6. Step 6: Final answer
   x = 1,365.27