Finding the Fourth Proportional to 2,228.61, 3,075.12 and 1,389.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,228.61 : 3,075.12 = 1,389.18 : x
2. Step 2: Convert to fraction form
   2,228.61/3,075.12 = 1,389.18/x
3. Step 3: Cross multiply
   2,228.61x = 3,075.12 × 1,389.18
4. Step 4: Simplify right side
   2,228.61x = 4,271,895.20
5. Step 5: Solve for x
   x = 4,271,895.20/2,228.61
6. Step 6: Final answer
   x = 1,916.84