Finding the Fourth Proportional to 12,990.47, 17,926.88 and 7,022.16

Step by Step Solution

1. Step 1: Write the proportion equation
   12,990.47 : 17,926.88 = 7,022.16 : x
2. Step 2: Convert to fraction form
   12,990.47/17,926.88 = 7,022.16/x
3. Step 3: Cross multiply
   12,990.47x = 17,926.88 × 7,022.16
4. Step 4: Simplify right side
   12,990.47x = 125,885,384.55
5. Step 5: Solve for x
   x = 125,885,384.55/12,990.47
6. Step 6: Final answer
   x = 9,690.60