Finding the Fourth Proportional to 42,987.61, 64,470.48 and 16,678

Step by Step Solution

1. Step 1: Write the proportion equation
   42,987.61 : 64,470.48 = 16,678 : x
2. Step 2: Convert to fraction form
   42,987.61/64,470.48 = 16,678/x
3. Step 3: Cross multiply
   42,987.61x = 64,470.48 × 16,678
4. Step 4: Simplify right side
   42,987.61x = 1,075,238,665.44
5. Step 5: Solve for x
   x = 1,075,238,665.44/42,987.61
6. Step 6: Final answer
   x = 25,012.76