Finding the Fourth Proportional to 3,405.78, 5,111.55 and 1,867.86

Step by Step Solution

1. Step 1: Write the proportion equation
   3,405.78 : 5,111.55 = 1,867.86 : x
2. Step 2: Convert to fraction form
   3,405.78/5,111.55 = 1,867.86/x
3. Step 3: Cross multiply
   3,405.78x = 5,111.55 × 1,867.86
4. Step 4: Simplify right side
   3,405.78x = 9,547,659.78
5. Step 5: Solve for x
   x = 9,547,659.78/3,405.78
6. Step 6: Final answer
   x = 2,803.37