Finding the Fourth Proportional to 1,131.23, 1,561.17 and 633.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.23 : 1,561.17 = 633.91 : x
2. Step 2: Convert to fraction form
   1,131.23/1,561.17 = 633.91/x
3. Step 3: Cross multiply
   1,131.23x = 1,561.17 × 633.91
4. Step 4: Simplify right side
   1,131.23x = 989,641.27
5. Step 5: Solve for x
   x = 989,641.27/1,131.23
6. Step 6: Final answer
   x = 874.84