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Finding the Fourth Proportional to 638.80, 879.60 and 481.66

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Solution

The fourth proportional to 638.80, 879.60 and 481.66 is: 663.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 879.60 = 481.66 : x
  2. Step 2: Convert to fraction form
    638.80/879.60 = 481.66/x
  3. Step 3: Cross multiply
    638.80x = 879.60 × 481.66
  4. Step 4: Simplify right side
    638.80x = 423,668.14
  5. Step 5: Solve for x
    x = 423,668.14/638.80
  6. Step 6: Final answer
    x = 663.23

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Double scale
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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.