Finding the Fourth Proportional to 3,936.51, 5,432.56 and 2,521.40

Step by Step Solution

1. Step 1: Write the proportion equation
   3,936.51 : 5,432.56 = 2,521.40 : x
2. Step 2: Convert to fraction form
   3,936.51/5,432.56 = 2,521.40/x
3. Step 3: Cross multiply
   3,936.51x = 5,432.56 × 2,521.40
4. Step 4: Simplify right side
   3,936.51x = 13,697,623.32
5. Step 5: Solve for x
   x = 13,697,623.32/3,936.51
6. Step 6: Final answer
   x = 3,479.64