Finding the Fourth Proportional to 1,636.82, 2,258.82 and 890.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,636.82 : 2,258.82 = 890.78 : x
2. Step 2: Convert to fraction form
   1,636.82/2,258.82 = 890.78/x
3. Step 3: Cross multiply
   1,636.82x = 2,258.82 × 890.78
4. Step 4: Simplify right side
   1,636.82x = 2,012,111.68
5. Step 5: Solve for x
   x = 2,012,111.68/1,636.82
6. Step 6: Final answer
   x = 1,229.28