Finding the Third Proportional to 99,778 and 217,012

Step by Step Solution

1. Step 1: Write the proportion equation
   99,778 : 217,012 = 217,012 : x
2. Step 2: Convert to fraction form
   99,778/217,012 = 217,012/x
3. Step 3: Cross multiply
   99,778x = 217,012 × 217,012
4. Step 4: Simplify right side
   99,778x = 47,094,208,144
5. Step 5: Solve for x
   x = 47,094,208,144/99,778
6. Step 6: Final answer
   x = 471,989.90