Finding the Third Proportional to 1,003.78 and 2,155.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.78 : 2,155.78 = 2,155.78 : x
2. Step 2: Convert to fraction form
   1,003.78/2,155.78 = 2,155.78/x
3. Step 3: Cross multiply
   1,003.78x = 2,155.78 × 2,155.78
4. Step 4: Simplify right side
   1,003.78x = 4,647,392.80
5. Step 5: Solve for x
   x = 4,647,392.80/1,003.78
6. Step 6: Final answer
   x = 4,629.89