Finding the Fourth Proportional to 42,922.30, 64,371.13 and 12,939.46

Step by Step Solution

1. Step 1: Write the proportion equation
   42,922.30 : 64,371.13 = 12,939.46 : x
2. Step 2: Convert to fraction form
   42,922.30/64,371.13 = 12,939.46/x
3. Step 3: Cross multiply
   42,922.30x = 64,371.13 × 12,939.46
4. Step 4: Simplify right side
   42,922.30x = 832,927,307.59
5. Step 5: Solve for x
   x = 832,927,307.59/42,922.30
6. Step 6: Final answer
   x = 19,405.47