Finding the Fourth Proportional to 1,661.89, 2,487.50 and 1,105.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,661.89 : 2,487.50 = 1,105.31 : x
2. Step 2: Convert to fraction form
   1,661.89/2,487.50 = 1,105.31/x
3. Step 3: Cross multiply
   1,661.89x = 2,487.50 × 1,105.31
4. Step 4: Simplify right side
   1,661.89x = 2,749,458.63
5. Step 5: Solve for x
   x = 2,749,458.63/1,661.89
6. Step 6: Final answer
   x = 1,654.42