Finding the Third Proportional to 9,142 and 13,780

Step by Step Solution

1. Step 1: Write the proportion equation
   9,142 : 13,780 = 13,780 : x
2. Step 2: Convert to fraction form
   9,142/13,780 = 13,780/x
3. Step 3: Cross multiply
   9,142x = 13,780 × 13,780
4. Step 4: Simplify right side
   9,142x = 189,888,400
5. Step 5: Solve for x
   x = 189,888,400/9,142
6. Step 6: Final answer
   x = 20,770.99