Finding the Fourth Proportional to 42,731.81, 64,103.79 and 13,152.11

Step by Step Solution

1. Step 1: Write the proportion equation
   42,731.81 : 64,103.79 = 13,152.11 : x
2. Step 2: Convert to fraction form
   42,731.81/64,103.79 = 13,152.11/x
3. Step 3: Cross multiply
   42,731.81x = 64,103.79 × 13,152.11
4. Step 4: Simplify right side
   42,731.81x = 843,100,097.50
5. Step 5: Solve for x
   x = 843,100,097.50/42,731.81
6. Step 6: Final answer
   x = 19,730.03