Finding the Third Proportional to 99,421,108,772 and 218,090,656,216

Step by Step Solution

1. Step 1: Write the proportion equation
   99,421,108,772 : 218,090,656,216 = 218,090,656,216 : x
2. Step 2: Convert to fraction form
   99,421,108,772/218,090,656,216 = 218,090,656,216/x
3. Step 3: Cross multiply
   99,421,108,772x = 218,090,656,216 × 218,090,656,216
4. Step 4: Simplify right side
   99,421,108,772x = 47,563,534,328,725,499,805,696
5. Step 5: Solve for x
   x = 47,563,534,328,725,499,805,696/99,421,108,772
6. Step 6: Final answer
   x = 478,404,786,631.40