Finding the Fourth Proportional to 1,103.90, 1,523.56 and 661.95

Step by Step Solution

1. Step 1: Write the proportion equation
   1,103.90 : 1,523.56 = 661.95 : x
2. Step 2: Convert to fraction form
   1,103.90/1,523.56 = 661.95/x
3. Step 3: Cross multiply
   1,103.90x = 1,523.56 × 661.95
4. Step 4: Simplify right side
   1,103.90x = 1,008,520.54
5. Step 5: Solve for x
   x = 1,008,520.54/1,103.90
6. Step 6: Final answer
   x = 913.60