Finding the Fourth Proportional to 2,087.40, 3,129.30 and 1,061.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,087.40 : 3,129.30 = 1,061.40 : x
2. Step 2: Convert to fraction form
   2,087.40/3,129.30 = 1,061.40/x
3. Step 3: Cross multiply
   2,087.40x = 3,129.30 × 1,061.40
4. Step 4: Simplify right side
   2,087.40x = 3,321,439.02
5. Step 5: Solve for x
   x = 3,321,439.02/2,087.40
6. Step 6: Final answer
   x = 1,591.18