Finding the Fourth Proportional to 42,781.41, 64,168.47 and 13,199.49

Step by Step Solution

1. Step 1: Write the proportion equation
   42,781.41 : 64,168.47 = 13,199.49 : x
2. Step 2: Convert to fraction form
   42,781.41/64,168.47 = 13,199.49/x
3. Step 3: Cross multiply
   42,781.41x = 64,168.47 × 13,199.49
4. Step 4: Simplify right side
   42,781.41x = 846,991,078.08
5. Step 5: Solve for x
   x = 846,991,078.08/42,781.41
6. Step 6: Final answer
   x = 19,798.11