Finding the Fourth Proportional to 11,990.56, 17,987.98 and 3,670.42

Step by Step Solution

1. Step 1: Write the proportion equation
   11,990.56 : 17,987.98 = 3,670.42 : x
2. Step 2: Convert to fraction form
   11,990.56/17,987.98 = 3,670.42/x
3. Step 3: Cross multiply
   11,990.56x = 17,987.98 × 3,670.42
4. Step 4: Simplify right side
   11,990.56x = 66,023,441.55
5. Step 5: Solve for x
   x = 66,023,441.55/11,990.56
6. Step 6: Final answer
   x = 5,506.29