Finding the Fourth Proportional to 42,791.79, 64,160.34 and 20,560.94

Step by Step Solution

1. Step 1: Write the proportion equation
   42,791.79 : 64,160.34 = 20,560.94 : x
2. Step 2: Convert to fraction form
   42,791.79/64,160.34 = 20,560.94/x
3. Step 3: Cross multiply
   42,791.79x = 64,160.34 × 20,560.94
4. Step 4: Simplify right side
   42,791.79x = 1,319,196,580.32
5. Step 5: Solve for x
   x = 1,319,196,580.32/42,791.79
6. Step 6: Final answer
   x = 30,828.26