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Finding the Fourth Proportional to 579.90, 869.13 and 287.09

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Solution

The fourth proportional to 579.90, 869.13 and 287.09 is: 430.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    579.90 : 869.13 = 287.09 : x
  2. Step 2: Convert to fraction form
    579.90/869.13 = 287.09/x
  3. Step 3: Cross multiply
    579.90x = 869.13 × 287.09
  4. Step 4: Simplify right side
    579.90x = 249,514.19
  5. Step 5: Solve for x
    x = 249,514.19/579.90
  6. Step 6: Final answer
    x = 430.27

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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.