Finding the Fourth Proportional to 2,428.67, 3,640.43 and 1,386.45

Step by Step Solution

1. Step 1: Write the proportion equation
   2,428.67 : 3,640.43 = 1,386.45 : x
2. Step 2: Convert to fraction form
   2,428.67/3,640.43 = 1,386.45/x
3. Step 3: Cross multiply
   2,428.67x = 3,640.43 × 1,386.45
4. Step 4: Simplify right side
   2,428.67x = 5,047,277.64
5. Step 5: Solve for x
   x = 5,047,277.64/2,428.67
6. Step 6: Final answer
   x = 2,078.20