Finding the Fourth Proportional to 2,385.65, 3,290.73 and 1,578.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,385.65 : 3,290.73 = 1,578.10 : x
2. Step 2: Convert to fraction form
   2,385.65/3,290.73 = 1,578.10/x
3. Step 3: Cross multiply
   2,385.65x = 3,290.73 × 1,578.10
4. Step 4: Simplify right side
   2,385.65x = 5,193,101.01
5. Step 5: Solve for x
   x = 5,193,101.01/2,385.65
6. Step 6: Final answer
   x = 2,176.81