Finding the Fourth Proportional to 1,131.42, 1,561.19 and 689.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.42 : 1,561.19 = 689.47 : x
2. Step 2: Convert to fraction form
   1,131.42/1,561.19 = 689.47/x
3. Step 3: Cross multiply
   1,131.42x = 1,561.19 × 689.47
4. Step 4: Simplify right side
   1,131.42x = 1,076,393.67
5. Step 5: Solve for x
   x = 1,076,393.67/1,131.42
6. Step 6: Final answer
   x = 951.37