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Finding the Fourth Proportional to 645.45, 890.71 and 350.71

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Solution

The fourth proportional to 645.45, 890.71 and 350.71 is: 483.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.45 : 890.71 = 350.71 : x
  2. Step 2: Convert to fraction form
    645.45/890.71 = 350.71/x
  3. Step 3: Cross multiply
    645.45x = 890.71 × 350.71
  4. Step 4: Simplify right side
    645.45x = 312,377.80
  5. Step 5: Solve for x
    x = 312,377.80/645.45
  6. Step 6: Final answer
    x = 483.97

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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.