Finding the Fourth Proportional to 42,723.05, 64,084.72 and 13,140.68

Step by Step Solution

1. Step 1: Write the proportion equation
   42,723.05 : 64,084.72 = 13,140.68 : x
2. Step 2: Convert to fraction form
   42,723.05/64,084.72 = 13,140.68/x
3. Step 3: Cross multiply
   42,723.05x = 64,084.72 × 13,140.68
4. Step 4: Simplify right side
   42,723.05x = 842,116,830.25
5. Step 5: Solve for x
   x = 842,116,830.25/42,723.05
6. Step 6: Final answer
   x = 19,711.07