Finding the Fourth Proportional to 1,643.89, 2,267.81 and 980.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,643.89 : 2,267.81 = 980.50 : x
2. Step 2: Convert to fraction form
   1,643.89/2,267.81 = 980.50/x
3. Step 3: Cross multiply
   1,643.89x = 2,267.81 × 980.50
4. Step 4: Simplify right side
   1,643.89x = 2,223,584.20
5. Step 5: Solve for x
   x = 2,223,584.20/1,643.89
6. Step 6: Final answer
   x = 1,352.64