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Finding the Fourth Proportional to 645.66, 890.16 and 383.58

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Solution

The fourth proportional to 645.66, 890.16 and 383.58 is: 528.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.66 : 890.16 = 383.58 : x
  2. Step 2: Convert to fraction form
    645.66/890.16 = 383.58/x
  3. Step 3: Cross multiply
    645.66x = 890.16 × 383.58
  4. Step 4: Simplify right side
    645.66x = 341,447.57
  5. Step 5: Solve for x
    x = 341,447.57/645.66
  6. Step 6: Final answer
    x = 528.83

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1.5x scale

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.