Finding the Fourth Proportional to 1,104.71, 1,659.56 and 643.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,104.71 : 1,659.56 = 643.59 : x
2. Step 2: Convert to fraction form
   1,104.71/1,659.56 = 643.59/x
3. Step 3: Cross multiply
   1,104.71x = 1,659.56 × 643.59
4. Step 4: Simplify right side
   1,104.71x = 1,068,073.00
5. Step 5: Solve for x
   x = 1,068,073.00/1,104.71
6. Step 6: Final answer
   x = 966.84