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Finding the Fourth Proportional to 645.39, 890.03 and 435.60

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Solution

The fourth proportional to 645.39, 890.03 and 435.60 is: 600.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.39 : 890.03 = 435.60 : x
  2. Step 2: Convert to fraction form
    645.39/890.03 = 435.60/x
  3. Step 3: Cross multiply
    645.39x = 890.03 × 435.60
  4. Step 4: Simplify right side
    645.39x = 387,694.89
  5. Step 5: Solve for x
    x = 387,694.89/645.39
  6. Step 6: Final answer
    x = 600.71

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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.