Finding the Fourth Proportional to 2,569.65, 3,546.10 and 1,390.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,569.65 : 3,546.10 = 1,390.72 : x
2. Step 2: Convert to fraction form
   2,569.65/3,546.10 = 1,390.72/x
3. Step 3: Cross multiply
   2,569.65x = 3,546.10 × 1,390.72
4. Step 4: Simplify right side
   2,569.65x = 4,931,607.51
5. Step 5: Solve for x
   x = 4,931,607.51/2,569.65
6. Step 6: Final answer
   x = 1,919.18