Finding the Third Proportional to 9,912 and 13,980

Step by Step Solution

1. Step 1: Write the proportion equation
   9,912 : 13,980 = 13,980 : x
2. Step 2: Convert to fraction form
   9,912/13,980 = 13,980/x
3. Step 3: Cross multiply
   9,912x = 13,980 × 13,980
4. Step 4: Simplify right side
   9,912x = 195,440,400
5. Step 5: Solve for x
   x = 195,440,400/9,912
6. Step 6: Final answer
   x = 19,717.55