Finding the Fourth Proportional to 1,386.45, 2,066.52 and 1,281.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.45 : 2,066.52 = 1,281.12 : x
2. Step 2: Convert to fraction form
   1,386.45/2,066.52 = 1,281.12/x
3. Step 3: Cross multiply
   1,386.45x = 2,066.52 × 1,281.12
4. Step 4: Simplify right side
   1,386.45x = 2,647,460.10
5. Step 5: Solve for x
   x = 2,647,460.10/1,386.45
6. Step 6: Final answer
   x = 1,909.52