Finding the Fourth Proportional to 3,689.12, 5,090.82 and 2,117.18

Step by Step Solution

1. Step 1: Write the proportion equation
   3,689.12 : 5,090.82 = 2,117.18 : x
2. Step 2: Convert to fraction form
   3,689.12/5,090.82 = 2,117.18/x
3. Step 3: Cross multiply
   3,689.12x = 5,090.82 × 2,117.18
4. Step 4: Simplify right side
   3,689.12x = 10,778,182.29
5. Step 5: Solve for x
   x = 10,778,182.29/3,689.12
6. Step 6: Final answer
   x = 2,921.61