Finding the Fourth Proportional to 1,108.77, 1,529.67 and 636.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,108.77 : 1,529.67 = 636.50 : x
2. Step 2: Convert to fraction form
   1,108.77/1,529.67 = 636.50/x
3. Step 3: Cross multiply
   1,108.77x = 1,529.67 × 636.50
4. Step 4: Simplify right side
   1,108.77x = 973,632.56
5. Step 5: Solve for x
   x = 973,632.56/1,108.77
6. Step 6: Final answer
   x = 878.12