Finding the Fourth Proportional to 1,131.28, 1,561.28 and 634.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.28 : 1,561.28 = 634.00 : x
2. Step 2: Convert to fraction form
   1,131.28/1,561.28 = 634.00/x
3. Step 3: Cross multiply
   1,131.28x = 1,561.28 × 634.00
4. Step 4: Simplify right side
   1,131.28x = 989,851.77
5. Step 5: Solve for x
   x = 989,851.77/1,131.28
6. Step 6: Final answer
   x = 874.98