Finding the Fourth Proportional to 1,643.50, 2,461.24 and 864.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,643.50 : 2,461.24 = 864.15 : x
2. Step 2: Convert to fraction form
   1,643.50/2,461.24 = 864.15/x
3. Step 3: Cross multiply
   1,643.50x = 2,461.24 × 864.15
4. Step 4: Simplify right side
   1,643.50x = 2,126,880.55
5. Step 5: Solve for x
   x = 2,126,880.55/1,643.50
6. Step 6: Final answer
   x = 1,294.12