Finding the Fourth Proportional to 1,185.63, 1,636.16 and 688.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185.63 : 1,636.16 = 688.56 : x
2. Step 2: Convert to fraction form
   1,185.63/1,636.16 = 688.56/x
3. Step 3: Cross multiply
   1,185.63x = 1,636.16 × 688.56
4. Step 4: Simplify right side
   1,185.63x = 1,126,590.89
5. Step 5: Solve for x
   x = 1,126,590.89/1,185.63
6. Step 6: Final answer
   x = 950.20