Finding the Fourth Proportional to 2,602.78, 3,591.90 and 1,423.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,602.78 : 3,591.90 = 1,423.90 : x
2. Step 2: Convert to fraction form
   2,602.78/3,591.90 = 1,423.90/x
3. Step 3: Cross multiply
   2,602.78x = 3,591.90 × 1,423.90
4. Step 4: Simplify right side
   2,602.78x = 5,114,506.41
5. Step 5: Solve for x
   x = 5,114,506.41/2,602.78
6. Step 6: Final answer
   x = 1,965.02