Finding the Fourth Proportional to 1,053.40, 1,454.61 and 661.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,053.40 : 1,454.61 = 661.10 : x
2. Step 2: Convert to fraction form
   1,053.40/1,454.61 = 661.10/x
3. Step 3: Cross multiply
   1,053.40x = 1,454.61 × 661.10
4. Step 4: Simplify right side
   1,053.40x = 961,642.67
5. Step 5: Solve for x
   x = 961,642.67/1,053.40
6. Step 6: Final answer
   x = 912.89