Finding the Fourth Proportional to 1,103.89, 1,522.50 and 661.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,103.89 : 1,522.50 = 661.72 : x
2. Step 2: Convert to fraction form
   1,103.89/1,522.50 = 661.72/x
3. Step 3: Cross multiply
   1,103.89x = 1,522.50 × 661.72
4. Step 4: Simplify right side
   1,103.89x = 1,007,468.70
5. Step 5: Solve for x
   x = 1,007,468.70/1,103.89
6. Step 6: Final answer
   x = 912.65