Finding the Fourth Proportional to 42,978.30, 64,470.54 and 17,993.18

Step by Step Solution

1. Step 1: Write the proportion equation
   42,978.30 : 64,470.54 = 17,993.18 : x
2. Step 2: Convert to fraction form
   42,978.30/64,470.54 = 17,993.18/x
3. Step 3: Cross multiply
   42,978.30x = 64,470.54 × 17,993.18
4. Step 4: Simplify right side
   42,978.30x = 1,160,030,030.92
5. Step 5: Solve for x
   x = 1,160,030,030.92/42,978.30
6. Step 6: Final answer
   x = 26,991.06