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Finding the Fourth Proportional to 645.90, 964.48 and 507.39

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Solution

The fourth proportional to 645.90, 964.48 and 507.39 is: 757.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.90 : 964.48 = 507.39 : x
  2. Step 2: Convert to fraction form
    645.90/964.48 = 507.39/x
  3. Step 3: Cross multiply
    645.90x = 964.48 × 507.39
  4. Step 4: Simplify right side
    645.90x = 489,364.97
  5. Step 5: Solve for x
    x = 489,364.97/645.90
  6. Step 6: Final answer
    x = 757.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.