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Finding the Fourth Proportional to 645.32, 890.26 and 383.20

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Solution

The fourth proportional to 645.32, 890.26 and 383.20 is: 528.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.32 : 890.26 = 383.20 : x
  2. Step 2: Convert to fraction form
    645.32/890.26 = 383.20/x
  3. Step 3: Cross multiply
    645.32x = 890.26 × 383.20
  4. Step 4: Simplify right side
    645.32x = 341,147.63
  5. Step 5: Solve for x
    x = 341,147.63/645.32
  6. Step 6: Final answer
    x = 528.65

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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.