Finding the Fourth Proportional to 1,439.74, 2,155.42 and 1,071.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.74 : 2,155.42 = 1,071.18 : x
2. Step 2: Convert to fraction form
   1,439.74/2,155.42 = 1,071.18/x
3. Step 3: Cross multiply
   1,439.74x = 2,155.42 × 1,071.18
4. Step 4: Simplify right side
   1,439.74x = 2,308,842.80
5. Step 5: Solve for x
   x = 2,308,842.80/1,439.74
6. Step 6: Final answer
   x = 1,603.65