Finding the Fourth Proportional to 1,185.75, 1,636.34 and 661.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185.75 : 1,636.34 = 661.91 : x
2. Step 2: Convert to fraction form
   1,185.75/1,636.34 = 661.91/x
3. Step 3: Cross multiply
   1,185.75x = 1,636.34 × 661.91
4. Step 4: Simplify right side
   1,185.75x = 1,083,098.32
5. Step 5: Solve for x
   x = 1,083,098.32/1,185.75
6. Step 6: Final answer
   x = 913.43