Home / 1,319.71-1,979.07-539.30

Finding the Fourth Proportional to 1,319.71, 1,979.07 and 539.30

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Solution

The fourth proportional to 1,319.71, 1,979.07 and 539.30 is: 808.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.71 : 1,979.07 = 539.30 : x
  2. Step 2: Convert to fraction form
    1,319.71/1,979.07 = 539.30/x
  3. Step 3: Cross multiply
    1,319.71x = 1,979.07 × 539.30
  4. Step 4: Simplify right side
    1,319.71x = 1,067,302.56
  5. Step 5: Solve for x
    x = 1,067,302.56/1,319.71
  6. Step 6: Final answer
    x = 808.74

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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.