Finding the Fourth Proportional to 1,200,445,653.69, 1,656,579,422.38 and 664,621,199.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,200,445,653.69 : 1,656,579,422.38 = 664,621,199.62 : x
2. Step 2: Convert to fraction form
   1,200,445,653.69/1,656,579,422.38 = 664,621,199.62/x
3. Step 3: Cross multiply
   1,200,445,653.69x = 1,656,579,422.38 × 664,621,199.62
4. Step 4: Simplify right side
   1,200,445,653.69x = 1,100,997,802,969,895,168
5. Step 5: Solve for x
   x = 1,100,997,802,969,895,168/1,200,445,653.69
6. Step 6: Final answer
   x = 917,157,556.94