Finding the Fourth Proportional to 11,888.17, 17,835.59 and 3,991.28

Step by Step Solution

1. Step 1: Write the proportion equation
   11,888.17 : 17,835.59 = 3,991.28 : x
2. Step 2: Convert to fraction form
   11,888.17/17,835.59 = 3,991.28/x
3. Step 3: Cross multiply
   11,888.17x = 17,835.59 × 3,991.28
4. Step 4: Simplify right side
   11,888.17x = 71,186,754.46
5. Step 5: Solve for x
   x = 71,186,754.46/11,888.17
6. Step 6: Final answer
   x = 5,988.03