Finding the Third Proportional to 128,865,831,124 and 261,406,111,752

Step by Step Solution

1. Step 1: Write the proportion equation
   128,865,831,124 : 261,406,111,752 = 261,406,111,752 : x
2. Step 2: Convert to fraction form
   128,865,831,124/261,406,111,752 = 261,406,111,752/x
3. Step 3: Cross multiply
   128,865,831,124x = 261,406,111,752 × 261,406,111,752
4. Step 4: Simplify right side
   128,865,831,124x = 68,333,155,261,299,111,755,776
5. Step 5: Solve for x
   x = 68,333,155,261,299,111,755,776/128,865,831,124
6. Step 6: Final answer
   x = 530,265,894,886.80