Finding the Fourth Proportional to 2,188.90, 3,284.72 and 890.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,188.90 : 3,284.72 = 890.38 : x
2. Step 2: Convert to fraction form
   2,188.90/3,284.72 = 890.38/x
3. Step 3: Cross multiply
   2,188.90x = 3,284.72 × 890.38
4. Step 4: Simplify right side
   2,188.90x = 2,924,648.99
5. Step 5: Solve for x
   x = 2,924,648.99/2,188.90
6. Step 6: Final answer
   x = 1,336.13