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Finding the Fourth Proportional to 645.44, 890.74 and 379.89

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Solution

The fourth proportional to 645.44, 890.74 and 379.89 is: 524.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.44 : 890.74 = 379.89 : x
  2. Step 2: Convert to fraction form
    645.44/890.74 = 379.89/x
  3. Step 3: Cross multiply
    645.44x = 890.74 × 379.89
  4. Step 4: Simplify right side
    645.44x = 338,383.22
  5. Step 5: Solve for x
    x = 338,383.22/645.44
  6. Step 6: Final answer
    x = 524.27

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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.