Finding the Third Proportional to 7,720 and 10,290

Step by Step Solution

1. Step 1: Write the proportion equation
   7,720 : 10,290 = 10,290 : x
2. Step 2: Convert to fraction form
   7,720/10,290 = 10,290/x
3. Step 3: Cross multiply
   7,720x = 10,290 × 10,290
4. Step 4: Simplify right side
   7,720x = 105,884,100
5. Step 5: Solve for x
   x = 105,884,100/7,720
6. Step 6: Final answer
   x = 13,715.56