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Finding the Fourth Proportional to 645.89, 968.88 and 387.65

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Solution

The fourth proportional to 645.89, 968.88 and 387.65 is: 581.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.89 : 968.88 = 387.65 : x
  2. Step 2: Convert to fraction form
    645.89/968.88 = 387.65/x
  3. Step 3: Cross multiply
    645.89x = 968.88 × 387.65
  4. Step 4: Simplify right side
    645.89x = 375,586.33
  5. Step 5: Solve for x
    x = 375,586.33/645.89
  6. Step 6: Final answer
    x = 581.51

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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.