Finding the Fourth Proportional to 43,145.47, 64,721 and 13,564.45

Step by Step Solution

1. Step 1: Write the proportion equation
   43,145.47 : 64,721 = 13,564.45 : x
2. Step 2: Convert to fraction form
   43,145.47/64,721 = 13,564.45/x
3. Step 3: Cross multiply
   43,145.47x = 64,721 × 13,564.45
4. Step 4: Simplify right side
   43,145.47x = 877,904,768.45
5. Step 5: Solve for x
   x = 877,904,768.45/43,145.47
6. Step 6: Final answer
   x = 20,347.55