Finding the Fourth Proportional to 42,798.84, 64,139.94 and 20,610.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42,798.84 : 64,139.94 = 20,610.60 : x
2. Step 2: Convert to fraction form
   42,798.84/64,139.94 = 20,610.60/x
3. Step 3: Cross multiply
   42,798.84x = 64,139.94 × 20,610.60
4. Step 4: Simplify right side
   42,798.84x = 1,321,962,647.36
5. Step 5: Solve for x
   x = 1,321,962,647.36/42,798.84
6. Step 6: Final answer
   x = 30,887.81