Finding the Fourth Proportional to 1,385.57, 1,912.28 and 889.65

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.57 : 1,912.28 = 889.65 : x
2. Step 2: Convert to fraction form
   1,385.57/1,912.28 = 889.65/x
3. Step 3: Cross multiply
   1,385.57x = 1,912.28 × 889.65
4. Step 4: Simplify right side
   1,385.57x = 1,701,255.45
5. Step 5: Solve for x
   x = 1,701,255.45/1,385.57
6. Step 6: Final answer
   x = 1,227.84