Finding the Fourth Proportional to 42,790.38, 64,217.07 and 20,301.10

Step by Step Solution

1. Step 1: Write the proportion equation
   42,790.38 : 64,217.07 = 20,301.10 : x
2. Step 2: Convert to fraction form
   42,790.38/64,217.07 = 20,301.10/x
3. Step 3: Cross multiply
   42,790.38x = 64,217.07 × 20,301.10
4. Step 4: Simplify right side
   42,790.38x = 1,303,677,159.78
5. Step 5: Solve for x
   x = 1,303,677,159.78/42,790.38
6. Step 6: Final answer
   x = 30,466.59