Finding the Fourth Proportional to 1,619.30, 2,186.78 and 1,619.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,619.30 : 2,186.78 = 1,619.30 : x
2. Step 2: Convert to fraction form
   1,619.30/2,186.78 = 1,619.30/x
3. Step 3: Cross multiply
   1,619.30x = 2,186.78 × 1,619.30
4. Step 4: Simplify right side
   1,619.30x = 3,541,052.85
5. Step 5: Solve for x
   x = 3,541,052.85/1,619.30
6. Step 6: Final answer
   x = 2,186.78