Finding the Third Proportional to 200,278 and 428,986

Step by Step Solution

1. Step 1: Write the proportion equation
   200,278 : 428,986 = 428,986 : x
2. Step 2: Convert to fraction form
   200,278/428,986 = 428,986/x
3. Step 3: Cross multiply
   200,278x = 428,986 × 428,986
4. Step 4: Simplify right side
   200,278x = 184,028,988,196
5. Step 5: Solve for x
   x = 184,028,988,196/200,278
6. Step 6: Final answer
   x = 918,867.71