Finding the Third Proportional to 99,578 and 215,003

Step by Step Solution

1. Step 1: Write the proportion equation
   99,578 : 215,003 = 215,003 : x
2. Step 2: Convert to fraction form
   99,578/215,003 = 215,003/x
3. Step 3: Cross multiply
   99,578x = 215,003 × 215,003
4. Step 4: Simplify right side
   99,578x = 46,226,290,009
5. Step 5: Solve for x
   x = 46,226,290,009/99,578
6. Step 6: Final answer
   x = 464,221.92