Finding the Third Proportional to 2,142.75 and 3,315.75

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.75 : 3,315.75 = 3,315.75 : x
2. Step 2: Convert to fraction form
   2,142.75/3,315.75 = 3,315.75/x
3. Step 3: Cross multiply
   2,142.75x = 3,315.75 × 3,315.75
4. Step 4: Simplify right side
   2,142.75x = 10,994,198.06
5. Step 5: Solve for x
   x = 10,994,198.06/2,142.75
6. Step 6: Final answer
   x = 5,130.88