Finding the Fourth Proportional to 13,224, 19,835.88 and 3,990

Step by Step Solution

1. Step 1: Write the proportion equation
   13,224 : 19,835.88 = 3,990 : x
2. Step 2: Convert to fraction form
   13,224/19,835.88 = 3,990/x
3. Step 3: Cross multiply
   13,224x = 19,835.88 × 3,990
4. Step 4: Simplify right side
   13,224x = 79,145,161.20
5. Step 5: Solve for x
   x = 79,145,161.20/13,224
6. Step 6: Final answer
   x = 5,984.96