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Finding the Fourth Proportional to 579.55, 869.40 and 287.20

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Solution

The fourth proportional to 579.55, 869.40 and 287.20 is: 430.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    579.55 : 869.40 = 287.20 : x
  2. Step 2: Convert to fraction form
    579.55/869.40 = 287.20/x
  3. Step 3: Cross multiply
    579.55x = 869.40 × 287.20
  4. Step 4: Simplify right side
    579.55x = 249,691.68
  5. Step 5: Solve for x
    x = 249,691.68/579.55
  6. Step 6: Final answer
    x = 430.84

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Similar ratio
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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.