Finding the Fourth Proportional to 2,103.96, 3,155.82 and 643.00

Step by Step Solution

1. Step 1: Write the proportion equation
   2,103.96 : 3,155.82 = 643.00 : x
2. Step 2: Convert to fraction form
   2,103.96/3,155.82 = 643.00/x
3. Step 3: Cross multiply
   2,103.96x = 3,155.82 × 643.00
4. Step 4: Simplify right side
   2,103.96x = 2,029,173.27
5. Step 5: Solve for x
   x = 2,029,173.27/2,103.96
6. Step 6: Final answer
   x = 964.46