Finding the Fourth Proportional to 2,208.72, 3,312.38 and 909.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,208.72 : 3,312.38 = 909.88 : x
2. Step 2: Convert to fraction form
   2,208.72/3,312.38 = 909.88/x
3. Step 3: Cross multiply
   2,208.72x = 3,312.38 × 909.88
4. Step 4: Simplify right side
   2,208.72x = 3,013,868.31
5. Step 5: Solve for x
   x = 3,013,868.31/2,208.72
6. Step 6: Final answer
   x = 1,364.53