Finding the Fourth Proportional to 42,895.40, 64,349.31 and 13,315.61

Step by Step Solution

1. Step 1: Write the proportion equation
   42,895.40 : 64,349.31 = 13,315.61 : x
2. Step 2: Convert to fraction form
   42,895.40/64,349.31 = 13,315.61/x
3. Step 3: Cross multiply
   42,895.40x = 64,349.31 × 13,315.61
4. Step 4: Simplify right side
   42,895.40x = 856,850,315.73
5. Step 5: Solve for x
   x = 856,850,315.73/42,895.40
6. Step 6: Final answer
   x = 19,975.34