Finding the Fourth Proportional to 3,945.50, 5,917.55 and 1,312.74

Step by Step Solution

1. Step 1: Write the proportion equation
   3,945.50 : 5,917.55 = 1,312.74 : x
2. Step 2: Convert to fraction form
   3,945.50/5,917.55 = 1,312.74/x
3. Step 3: Cross multiply
   3,945.50x = 5,917.55 × 1,312.74
4. Step 4: Simplify right side
   3,945.50x = 7,768,204.59
5. Step 5: Solve for x
   x = 7,768,204.59/3,945.50
6. Step 6: Final answer
   x = 1,968.88