Finding the Fourth Proportional to 1,386.82, 1,914.08 and 890.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.82 : 1,914.08 = 890.09 : x
2. Step 2: Convert to fraction form
   1,386.82/1,914.08 = 890.09/x
3. Step 3: Cross multiply
   1,386.82x = 1,914.08 × 890.09
4. Step 4: Simplify right side
   1,386.82x = 1,703,701.63
5. Step 5: Solve for x
   x = 1,703,701.63/1,386.82
6. Step 6: Final answer
   x = 1,228.49