Finding the Fourth Proportional to 1,185.30, 1,635.72 and 688.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185.30 : 1,635.72 = 688.23 : x
2. Step 2: Convert to fraction form
   1,185.30/1,635.72 = 688.23/x
3. Step 3: Cross multiply
   1,185.30x = 1,635.72 × 688.23
4. Step 4: Simplify right side
   1,185.30x = 1,125,751.58
5. Step 5: Solve for x
   x = 1,125,751.58/1,185.30
6. Step 6: Final answer
   x = 949.76