Finding the Fourth Proportional to 19,870.72, 27,421.47 and 10,918.01

Step by Step Solution

1. Step 1: Write the proportion equation
   19,870.72 : 27,421.47 = 10,918.01 : x
2. Step 2: Convert to fraction form
   19,870.72/27,421.47 = 10,918.01/x
3. Step 3: Cross multiply
   19,870.72x = 27,421.47 × 10,918.01
4. Step 4: Simplify right side
   19,870.72x = 299,387,952.23
5. Step 5: Solve for x
   x = 299,387,952.23/19,870.72
6. Step 6: Final answer
   x = 15,066.79