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Finding the Fourth Proportional to 645.40, 965.70 and 587.80

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Solution

The fourth proportional to 645.40, 965.70 and 587.80 is: 879.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.40 : 965.70 = 587.80 : x
  2. Step 2: Convert to fraction form
    645.40/965.70 = 587.80/x
  3. Step 3: Cross multiply
    645.40x = 965.70 × 587.80
  4. Step 4: Simplify right side
    645.40x = 567,638.46
  5. Step 5: Solve for x
    x = 567,638.46/645.40
  6. Step 6: Final answer
    x = 879.51

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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.