Finding the Fourth Proportional to 2,284.88, 3,153.60 and 1,290.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,284.88 : 3,153.60 = 1,290.20 : x
2. Step 2: Convert to fraction form
   2,284.88/3,153.60 = 1,290.20/x
3. Step 3: Cross multiply
   2,284.88x = 3,153.60 × 1,290.20
4. Step 4: Simplify right side
   2,284.88x = 4,068,774.72
5. Step 5: Solve for x
   x = 4,068,774.72/2,284.88
6. Step 6: Final answer
   x = 1,780.74