Finding the Fourth Proportional to 2,561.72, 3,838.50 and 1,909.16

Step by Step Solution

1. Step 1: Write the proportion equation
   2,561.72 : 3,838.50 = 1,909.16 : x
2. Step 2: Convert to fraction form
   2,561.72/3,838.50 = 1,909.16/x
3. Step 3: Cross multiply
   2,561.72x = 3,838.50 × 1,909.16
4. Step 4: Simplify right side
   2,561.72x = 7,328,310.66
5. Step 5: Solve for x
   x = 7,328,310.66/2,561.72
6. Step 6: Final answer
   x = 2,860.70