Finding the Fourth Proportional to 1,152.47, 1,590.42 and 686.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,152.47 : 1,590.42 = 686.63 : x
2. Step 2: Convert to fraction form
   1,152.47/1,590.42 = 686.63/x
3. Step 3: Cross multiply
   1,152.47x = 1,590.42 × 686.63
4. Step 4: Simplify right side
   1,152.47x = 1,092,022.13
5. Step 5: Solve for x
   x = 1,092,022.13/1,152.47
6. Step 6: Final answer
   x = 947.55