Finding the Fourth Proportional to 35,910.72, 53,868 and 13,720

Step by Step Solution

1. Step 1: Write the proportion equation
   35,910.72 : 53,868 = 13,720 : x
2. Step 2: Convert to fraction form
   35,910.72/53,868 = 13,720/x
3. Step 3: Cross multiply
   35,910.72x = 53,868 × 13,720
4. Step 4: Simplify right side
   35,910.72x = 739,068,960
5. Step 5: Solve for x
   x = 739,068,960/35,910.72
6. Step 6: Final answer
   x = 20,580.73