Finding the Fourth Proportional to 3,990.62, 5,507.60 and 2,312.55

Step by Step Solution

1. Step 1: Write the proportion equation
   3,990.62 : 5,507.60 = 2,312.55 : x
2. Step 2: Convert to fraction form
   3,990.62/5,507.60 = 2,312.55/x
3. Step 3: Cross multiply
   3,990.62x = 5,507.60 × 2,312.55
4. Step 4: Simplify right side
   3,990.62x = 12,736,588.82
5. Step 5: Solve for x
   x = 12,736,588.82/3,990.62
6. Step 6: Final answer
   x = 3,191.63