Finding the Fourth Proportional to 42,915,145.60, 64,384,123.20 and 18,643,657.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42,915,145.60 : 64,384,123.20 = 18,643,657.60 : x
2. Step 2: Convert to fraction form
   42,915,145.60/64,384,123.20 = 18,643,657.60/x
3. Step 3: Cross multiply
   42,915,145.60x = 64,384,123.20 × 18,643,657.60
4. Step 4: Simplify right side
   42,915,145.60x = 1,200,355,547,817,016.50
5. Step 5: Solve for x
   x = 1,200,355,547,817,016.50/42,915,145.60
6. Step 6: Final answer
   x = 27,970,441.00