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Finding the Fourth Proportional to 645.38, 890.88 and 379.94

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Solution

The fourth proportional to 645.38, 890.88 and 379.94 is: 524.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.38 : 890.88 = 379.94 : x
  2. Step 2: Convert to fraction form
    645.38/890.88 = 379.94/x
  3. Step 3: Cross multiply
    645.38x = 890.88 × 379.94
  4. Step 4: Simplify right side
    645.38x = 338,480.95
  5. Step 5: Solve for x
    x = 338,480.95/645.38
  6. Step 6: Final answer
    x = 524.47

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Double scale
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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.