Finding the Fourth Proportional to 1,405.50, 2,108.52 and 636

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.50 : 2,108.52 = 636 : x
2. Step 2: Convert to fraction form
   1,405.50/2,108.52 = 636/x
3. Step 3: Cross multiply
   1,405.50x = 2,108.52 × 636
4. Step 4: Simplify right side
   1,405.50x = 1,341,018.72
5. Step 5: Solve for x
   x = 1,341,018.72/1,405.50
6. Step 6: Final answer
   x = 954.12