Home / 3,986.40-5,981.36-1,391.20

Finding the Fourth Proportional to 3,986.40, 5,981.36 and 1,391.20

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Solution

The fourth proportional to 3,986.40, 5,981.36 and 1,391.20 is: 2,087.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,986.40 : 5,981.36 = 1,391.20 : x
  2. Step 2: Convert to fraction form
    3,986.40/5,981.36 = 1,391.20/x
  3. Step 3: Cross multiply
    3,986.40x = 5,981.36 × 1,391.20
  4. Step 4: Simplify right side
    3,986.40x = 8,321,268.03
  5. Step 5: Solve for x
    x = 8,321,268.03/3,986.40
  6. Step 6: Final answer
    x = 2,087.41

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.