Finding the Fourth Proportional to 42,789.58, 64,215.90 and 20,300.33

Step by Step Solution

1. Step 1: Write the proportion equation
   42,789.58 : 64,215.90 = 20,300.33 : x
2. Step 2: Convert to fraction form
   42,789.58/64,215.90 = 20,300.33/x
3. Step 3: Cross multiply
   42,789.58x = 64,215.90 × 20,300.33
4. Step 4: Simplify right side
   42,789.58x = 1,303,603,961.25
5. Step 5: Solve for x
   x = 1,303,603,961.25/42,789.58
6. Step 6: Final answer
   x = 30,465.45