Finding the Third Proportional to 128,865,831,120 and 261,406,111,744

Step by Step Solution

1. Step 1: Write the proportion equation
   128,865,831,120 : 261,406,111,744 = 261,406,111,744 : x
2. Step 2: Convert to fraction form
   128,865,831,120/261,406,111,744 = 261,406,111,744/x
3. Step 3: Cross multiply
   128,865,831,120x = 261,406,111,744 × 261,406,111,744
4. Step 4: Simplify right side
   128,865,831,120x = 68,333,155,257,116,610,527,232
5. Step 5: Solve for x
   x = 68,333,155,257,116,610,527,232/128,865,831,120
6. Step 6: Final answer
   x = 530,265,894,870.80