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Finding the Fourth Proportional to 421.11, 581.04 and 255.39

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Solution

The fourth proportional to 421.11, 581.04 and 255.39 is: 352.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.11 : 581.04 = 255.39 : x
  2. Step 2: Convert to fraction form
    421.11/581.04 = 255.39/x
  3. Step 3: Cross multiply
    421.11x = 581.04 × 255.39
  4. Step 4: Simplify right side
    421.11x = 148,391.81
  5. Step 5: Solve for x
    x = 148,391.81/421.11
  6. Step 6: Final answer
    x = 352.38

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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.