Finding the Fourth Proportional to 1,131.94, 1,696.26 and 643.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.94 : 1,696.26 = 643.96 : x
2. Step 2: Convert to fraction form
   1,131.94/1,696.26 = 643.96/x
3. Step 3: Cross multiply
   1,131.94x = 1,696.26 × 643.96
4. Step 4: Simplify right side
   1,131.94x = 1,092,323.59
5. Step 5: Solve for x
   x = 1,092,323.59/1,131.94
6. Step 6: Final answer
   x = 965.00