Finding the Fourth Proportional to 1,389.16, 1,916.85 and 1,180.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.16 : 1,916.85 = 1,180.18 : x
2. Step 2: Convert to fraction form
   1,389.16/1,916.85 = 1,180.18/x
3. Step 3: Cross multiply
   1,389.16x = 1,916.85 × 1,180.18
4. Step 4: Simplify right side
   1,389.16x = 2,262,228.03
5. Step 5: Solve for x
   x = 2,262,228.03/1,389.16
6. Step 6: Final answer
   x = 1,628.49