Finding the Fourth Proportional to 2,185.78, 3,019.80 and 1,857.64

Step by Step Solution

1. Step 1: Write the proportion equation
   2,185.78 : 3,019.80 = 1,857.64 : x
2. Step 2: Convert to fraction form
   2,185.78/3,019.80 = 1,857.64/x
3. Step 3: Cross multiply
   2,185.78x = 3,019.80 × 1,857.64
4. Step 4: Simplify right side
   2,185.78x = 5,609,701.27
5. Step 5: Solve for x
   x = 5,609,701.27/2,185.78
6. Step 6: Final answer
   x = 2,566.45