Finding the Fourth Proportional to 1,131.45, 1,561.42 and 634.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.45 : 1,561.42 = 634.09 : x
2. Step 2: Convert to fraction form
   1,131.45/1,561.42 = 634.09/x
3. Step 3: Cross multiply
   1,131.45x = 1,561.42 × 634.09
4. Step 4: Simplify right side
   1,131.45x = 990,077.70
5. Step 5: Solve for x
   x = 990,077.70/1,131.45
6. Step 6: Final answer
   x = 875.05