Finding the Fourth Proportional to 397,501,480.76, 548,570,147.87 and 221,300,667.18

Step by Step Solution

1. Step 1: Write the proportion equation
   397,501,480.76 : 548,570,147.87 = 221,300,667.18 : x
2. Step 2: Convert to fraction form
   397,501,480.76/548,570,147.87 = 221,300,667.18/x
3. Step 3: Cross multiply
   397,501,480.76x = 548,570,147.87 × 221,300,667.18
4. Step 4: Simplify right side
   397,501,480.76x = 121,398,939,718,662,256
5. Step 5: Solve for x
   x = 121,398,939,718,662,256/397,501,480.76
6. Step 6: Final answer
   x = 305,404,999.97