Finding the Fourth Proportional to 2,817.56, 3,887.52 and 2,117.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,817.56 : 3,887.52 = 2,117.72 : x
2. Step 2: Convert to fraction form
   2,817.56/3,887.52 = 2,117.72/x
3. Step 3: Cross multiply
   2,817.56x = 3,887.52 × 2,117.72
4. Step 4: Simplify right side
   2,817.56x = 8,232,678.85
5. Step 5: Solve for x
   x = 8,232,678.85/2,817.56
6. Step 6: Final answer
   x = 2,921.92