Home / 1,319.38-1,979.46-539.69

Finding the Fourth Proportional to 1,319.38, 1,979.46 and 539.69

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Solution

The fourth proportional to 1,319.38, 1,979.46 and 539.69 is: 809.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.38 : 1,979.46 = 539.69 : x
  2. Step 2: Convert to fraction form
    1,319.38/1,979.46 = 539.69/x
  3. Step 3: Cross multiply
    1,319.38x = 1,979.46 × 539.69
  4. Step 4: Simplify right side
    1,319.38x = 1,068,291.96
  5. Step 5: Solve for x
    x = 1,068,291.96/1,319.38
  6. Step 6: Final answer
    x = 809.69

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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.