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Finding the Fourth Proportional to 638.76, 880.86 and 417.24

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Solution

The fourth proportional to 638.76, 880.86 and 417.24 is: 575.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.76 : 880.86 = 417.24 : x
  2. Step 2: Convert to fraction form
    638.76/880.86 = 417.24/x
  3. Step 3: Cross multiply
    638.76x = 880.86 × 417.24
  4. Step 4: Simplify right side
    638.76x = 367,530.03
  5. Step 5: Solve for x
    x = 367,530.03/638.76
  6. Step 6: Final answer
    x = 575.38

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Double scale
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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.