Finding the Third Proportional to 213,117 and 318,216.75

Step by Step Solution

1. Step 1: Write the proportion equation
   213,117 : 318,216.75 = 318,216.75 : x
2. Step 2: Convert to fraction form
   213,117/318,216.75 = 318,216.75/x
3. Step 3: Cross multiply
   213,117x = 318,216.75 × 318,216.75
4. Step 4: Simplify right side
   213,117x = 101,261,899,980.56
5. Step 5: Solve for x
   x = 101,261,899,980.56/213,117
6. Step 6: Final answer
   x = 475,146.98