Finding the Third Proportional to 149,721 and 215,216

Step by Step Solution

1. Step 1: Write the proportion equation
   149,721 : 215,216 = 215,216 : x
2. Step 2: Convert to fraction form
   149,721/215,216 = 215,216/x
3. Step 3: Cross multiply
   149,721x = 215,216 × 215,216
4. Step 4: Simplify right side
   149,721x = 46,317,926,656
5. Step 5: Solve for x
   x = 46,317,926,656/149,721
6. Step 6: Final answer
   x = 309,361.59