Finding the Fourth Proportional to 1,131.50, 1,561.50 and 634.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.50 : 1,561.50 = 634.21 : x
2. Step 2: Convert to fraction form
   1,131.50/1,561.50 = 634.21/x
3. Step 3: Cross multiply
   1,131.50x = 1,561.50 × 634.21
4. Step 4: Simplify right side
   1,131.50x = 990,315.01
5. Step 5: Solve for x
   x = 990,315.01/1,131.50
6. Step 6: Final answer
   x = 875.22