Finding the Fourth Proportional to 42,940.30, 64,421.43 and 13,358.39

Step by Step Solution

1. Step 1: Write the proportion equation
   42,940.30 : 64,421.43 = 13,358.39 : x
2. Step 2: Convert to fraction form
   42,940.30/64,421.43 = 13,358.39/x
3. Step 3: Cross multiply
   42,940.30x = 64,421.43 × 13,358.39
4. Step 4: Simplify right side
   42,940.30x = 860,566,586.30
5. Step 5: Solve for x
   x = 860,566,586.30/42,940.30
6. Step 6: Final answer
   x = 20,041.00