Finding the Fourth Proportional to 42,915,139.60, 64,384,114.20 and 18,643,651.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42,915,139.60 : 64,384,114.20 = 18,643,651.60 : x
2. Step 2: Convert to fraction form
   42,915,139.60/64,384,114.20 = 18,643,651.60/x
3. Step 3: Cross multiply
   42,915,139.60x = 64,384,114.20 × 18,643,651.60
4. Step 4: Simplify right side
   42,915,139.60x = 1,200,354,993,719,412.75
5. Step 5: Solve for x
   x = 1,200,354,993,719,412.75/42,915,139.60
6. Step 6: Final answer
   x = 27,970,431.99