Finding the Fourth Proportional to 2,309.60, 3,462.15 and 1,321.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,309.60 : 3,462.15 = 1,321.40 : x
2. Step 2: Convert to fraction form
   2,309.60/3,462.15 = 1,321.40/x
3. Step 3: Cross multiply
   2,309.60x = 3,462.15 × 1,321.40
4. Step 4: Simplify right side
   2,309.60x = 4,574,885.01
5. Step 5: Solve for x
   x = 4,574,885.01/2,309.60
6. Step 6: Final answer
   x = 1,980.81