Finding the Third Proportional to 390,015 and 598,645.69

Step by Step Solution

1. Step 1: Write the proportion equation
   390,015 : 598,645.69 = 598,645.69 : x
2. Step 2: Convert to fraction form
   390,015/598,645.69 = 598,645.69/x
3. Step 3: Cross multiply
   390,015x = 598,645.69 × 598,645.69
4. Step 4: Simplify right side
   390,015x = 358,376,659,162.35
5. Step 5: Solve for x
   x = 358,376,659,162.35/390,015
6. Step 6: Final answer
   x = 918,879.17