Finding the Fourth Proportional to 8,987.43, 12,402.69 and 5,211.33

Step by Step Solution

1. Step 1: Write the proportion equation
   8,987.43 : 12,402.69 = 5,211.33 : x
2. Step 2: Convert to fraction form
   8,987.43/12,402.69 = 5,211.33/x
3. Step 3: Cross multiply
   8,987.43x = 12,402.69 × 5,211.33
4. Step 4: Simplify right side
   8,987.43x = 64,634,510.48
5. Step 5: Solve for x
   x = 64,634,510.48/8,987.43
6. Step 6: Final answer
   x = 7,191.66