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Finding the Fourth Proportional to 568.40, 783.24 and 420.80

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Solution

The fourth proportional to 568.40, 783.24 and 420.80 is: 579.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    568.40 : 783.24 = 420.80 : x
  2. Step 2: Convert to fraction form
    568.40/783.24 = 420.80/x
  3. Step 3: Cross multiply
    568.40x = 783.24 × 420.80
  4. Step 4: Simplify right side
    568.40x = 329,587.39
  5. Step 5: Solve for x
    x = 329,587.39/568.40
  6. Step 6: Final answer
    x = 579.85

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.