Finding the Third Proportional to 1,687.61 and 3,620.11

Step by Step Solution

1. Step 1: Write the proportion equation
   1,687.61 : 3,620.11 = 3,620.11 : x
2. Step 2: Convert to fraction form
   1,687.61/3,620.11 = 3,620.11/x
3. Step 3: Cross multiply
   1,687.61x = 3,620.11 × 3,620.11
4. Step 4: Simplify right side
   1,687.61x = 13,105,191.89
5. Step 5: Solve for x
   x = 13,105,191.89/1,687.61
6. Step 6: Final answer
   x = 7,765.55