Finding the Fourth Proportional to 1,641.12, 2,459.55 and 666.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,641.12 : 2,459.55 = 666.69 : x
2. Step 2: Convert to fraction form
   1,641.12/2,459.55 = 666.69/x
3. Step 3: Cross multiply
   1,641.12x = 2,459.55 × 666.69
4. Step 4: Simplify right side
   1,641.12x = 1,639,757.39
5. Step 5: Solve for x
   x = 1,639,757.39/1,641.12
6. Step 6: Final answer
   x = 999.17