Finding the Fourth Proportional to 42,003.40, 62,918.70 and 21,238.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42,003.40 : 62,918.70 = 21,238.60 : x
2. Step 2: Convert to fraction form
   42,003.40/62,918.70 = 21,238.60/x
3. Step 3: Cross multiply
   42,003.40x = 62,918.70 × 21,238.60
4. Step 4: Simplify right side
   42,003.40x = 1,336,305,101.82
5. Step 5: Solve for x
   x = 1,336,305,101.82/42,003.40
6. Step 6: Final answer
   x = 31,814.21