Finding the Fourth Proportional to 20,888.28, 31,343.76 and 13,851

Step by Step Solution

1. Step 1: Write the proportion equation
   20,888.28 : 31,343.76 = 13,851 : x
2. Step 2: Convert to fraction form
   20,888.28/31,343.76 = 13,851/x
3. Step 3: Cross multiply
   20,888.28x = 31,343.76 × 13,851
4. Step 4: Simplify right side
   20,888.28x = 434,142,419.76
5. Step 5: Solve for x
   x = 434,142,419.76/20,888.28
6. Step 6: Final answer
   x = 20,784.02