Finding the Fourth Proportional to 3,920.40, 5,409.98 and 2,152.03

Step by Step Solution

1. Step 1: Write the proportion equation
   3,920.40 : 5,409.98 = 2,152.03 : x
2. Step 2: Convert to fraction form
   3,920.40/5,409.98 = 2,152.03/x
3. Step 3: Cross multiply
   3,920.40x = 5,409.98 × 2,152.03
4. Step 4: Simplify right side
   3,920.40x = 11,642,428.50
5. Step 5: Solve for x
   x = 11,642,428.50/3,920.40
6. Step 6: Final answer
   x = 2,969.71