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Finding the Fourth Proportional to 628.80, 865.80 and 564

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Solution

The fourth proportional to 628.80, 865.80 and 564 is: 776.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 865.80 = 564 : x
  2. Step 2: Convert to fraction form
    628.80/865.80 = 564/x
  3. Step 3: Cross multiply
    628.80x = 865.80 × 564
  4. Step 4: Simplify right side
    628.80x = 488,311.20
  5. Step 5: Solve for x
    x = 488,311.20/628.80
  6. Step 6: Final answer
    x = 776.58

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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.