Finding the Third Proportional to 10,618 and 12,988

Step by Step Solution

1. Step 1: Write the proportion equation
   10,618 : 12,988 = 12,988 : x
2. Step 2: Convert to fraction form
   10,618/12,988 = 12,988/x
3. Step 3: Cross multiply
   10,618x = 12,988 × 12,988
4. Step 4: Simplify right side
   10,618x = 168,688,144
5. Step 5: Solve for x
   x = 168,688,144/10,618
6. Step 6: Final answer
   x = 15,887.00