Finding the Fourth Proportional to 42,698.28, 64,048.19 and 13,116.38

Step by Step Solution

1. Step 1: Write the proportion equation
   42,698.28 : 64,048.19 = 13,116.38 : x
2. Step 2: Convert to fraction form
   42,698.28/64,048.19 = 13,116.38/x
3. Step 3: Cross multiply
   42,698.28x = 64,048.19 × 13,116.38
4. Step 4: Simplify right side
   42,698.28x = 840,080,012.53
5. Step 5: Solve for x
   x = 840,080,012.53/42,698.28
6. Step 6: Final answer
   x = 19,674.80