Finding the Fourth Proportional to 21,020.32, 31,528.04 and 5,436.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,020.32 : 31,528.04 = 5,436.72 : x
2. Step 2: Convert to fraction form
   21,020.32/31,528.04 = 5,436.72/x
3. Step 3: Cross multiply
   21,020.32x = 31,528.04 × 5,436.72
4. Step 4: Simplify right side
   21,020.32x = 171,409,125.63
5. Step 5: Solve for x
   x = 171,409,125.63/21,020.32
6. Step 6: Final answer
   x = 8,154.45