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Finding the Fourth Proportional to 645.33, 890.76 and 480.09

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Solution

The fourth proportional to 645.33, 890.76 and 480.09 is: 662.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.33 : 890.76 = 480.09 : x
  2. Step 2: Convert to fraction form
    645.33/890.76 = 480.09/x
  3. Step 3: Cross multiply
    645.33x = 890.76 × 480.09
  4. Step 4: Simplify right side
    645.33x = 427,640.51
  5. Step 5: Solve for x
    x = 427,640.51/645.33
  6. Step 6: Final answer
    x = 662.67

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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.