Finding the Third Proportional to 290,839,144 and 636,405,848

Step by Step Solution

1. Step 1: Write the proportion equation
   290,839,144 : 636,405,848 = 636,405,848 : x
2. Step 2: Convert to fraction form
   290,839,144/636,405,848 = 636,405,848/x
3. Step 3: Cross multiply
   290,839,144x = 636,405,848 × 636,405,848
4. Step 4: Simplify right side
   290,839,144x = 405,012,403,368,599,104
5. Step 5: Solve for x
   x = 405,012,403,368,599,104/290,839,144
6. Step 6: Final answer
   x = 1,392,564,968.38