Finding the Fourth Proportional to 3,613.98, 4,987.17 and 2,121.86

Step by Step Solution

1. Step 1: Write the proportion equation
   3,613.98 : 4,987.17 = 2,121.86 : x
2. Step 2: Convert to fraction form
   3,613.98/4,987.17 = 2,121.86/x
3. Step 3: Cross multiply
   3,613.98x = 4,987.17 × 2,121.86
4. Step 4: Simplify right side
   3,613.98x = 10,582,076.54
5. Step 5: Solve for x
   x = 10,582,076.54/3,613.98
6. Step 6: Final answer
   x = 2,928.09