Finding the Fourth Proportional to 1,109.49, 1,531.27 and 661.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.49 : 1,531.27 = 661.38 : x
2. Step 2: Convert to fraction form
   1,109.49/1,531.27 = 661.38/x
3. Step 3: Cross multiply
   1,109.49x = 1,531.27 × 661.38
4. Step 4: Simplify right side
   1,109.49x = 1,012,751.35
5. Step 5: Solve for x
   x = 1,012,751.35/1,109.49
6. Step 6: Final answer
   x = 912.81