Finding the Fourth Proportional to 2,621.70, 3,927.42 and 1,390.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,621.70 : 3,927.42 = 1,390.50 : x
2. Step 2: Convert to fraction form
   2,621.70/3,927.42 = 1,390.50/x
3. Step 3: Cross multiply
   2,621.70x = 3,927.42 × 1,390.50
4. Step 4: Simplify right side
   2,621.70x = 5,461,077.51
5. Step 5: Solve for x
   x = 5,461,077.51/2,621.70
6. Step 6: Final answer
   x = 2,083.03