Finding the Fourth Proportional to 2,639.92, 3,642.50 and 1,577.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,639.92 : 3,642.50 = 1,577.40 : x
2. Step 2: Convert to fraction form
   2,639.92/3,642.50 = 1,577.40/x
3. Step 3: Cross multiply
   2,639.92x = 3,642.50 × 1,577.40
4. Step 4: Simplify right side
   2,639.92x = 5,745,679.50
5. Step 5: Solve for x
   x = 5,745,679.50/2,639.92
6. Step 6: Final answer
   x = 2,176.46