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Finding the Fourth Proportional to 645.45, 890.60 and 383.55

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Solution

The fourth proportional to 645.45, 890.60 and 383.55 is: 529.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.45 : 890.60 = 383.55 : x
  2. Step 2: Convert to fraction form
    645.45/890.60 = 383.55/x
  3. Step 3: Cross multiply
    645.45x = 890.60 × 383.55
  4. Step 4: Simplify right side
    645.45x = 341,587.71
  5. Step 5: Solve for x
    x = 341,587.71/645.45
  6. Step 6: Final answer
    x = 529.22

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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.