Finding the Fourth Proportional to 1,131.64, 1,561.72 and 634.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.64 : 1,561.72 = 634.28 : x
2. Step 2: Convert to fraction form
   1,131.64/1,561.72 = 634.28/x
3. Step 3: Cross multiply
   1,131.64x = 1,561.72 × 634.28
4. Step 4: Simplify right side
   1,131.64x = 990,567.76
5. Step 5: Solve for x
   x = 990,567.76/1,131.64
6. Step 6: Final answer
   x = 875.34