Finding the Fourth Proportional to 42,839.86, 64,262.53 and 13,255.22

Step by Step Solution

1. Step 1: Write the proportion equation
   42,839.86 : 64,262.53 = 13,255.22 : x
2. Step 2: Convert to fraction form
   42,839.86/64,262.53 = 13,255.22/x
3. Step 3: Cross multiply
   42,839.86x = 64,262.53 × 13,255.22
4. Step 4: Simplify right side
   42,839.86x = 851,813,972.91
5. Step 5: Solve for x
   x = 851,813,972.91/42,839.86
6. Step 6: Final answer
   x = 19,883.68