Home / 1,319.12-1,979.81-539.55

Finding the Fourth Proportional to 1,319.12, 1,979.81 and 539.55

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Solution

The fourth proportional to 1,319.12, 1,979.81 and 539.55 is: 809.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.12 : 1,979.81 = 539.55 : x
  2. Step 2: Convert to fraction form
    1,319.12/1,979.81 = 539.55/x
  3. Step 3: Cross multiply
    1,319.12x = 1,979.81 × 539.55
  4. Step 4: Simplify right side
    1,319.12x = 1,068,206.49
  5. Step 5: Solve for x
    x = 1,068,206.49/1,319.12
  6. Step 6: Final answer
    x = 809.79

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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.