Finding the Fourth Proportional to 1,908.40, 2,632.15 and 1,643.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,908.40 : 2,632.15 = 1,643.30 : x
2. Step 2: Convert to fraction form
   1,908.40/2,632.15 = 1,643.30/x
3. Step 3: Cross multiply
   1,908.40x = 2,632.15 × 1,643.30
4. Step 4: Simplify right side
   1,908.40x = 4,325,390.72
5. Step 5: Solve for x
   x = 4,325,390.72/1,908.40
6. Step 6: Final answer
   x = 2,266.50