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Finding the Fourth Proportional to 420.76, 581.34 and 321.54

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Solution

The fourth proportional to 420.76, 581.34 and 321.54 is: 444.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.76 : 581.34 = 321.54 : x
  2. Step 2: Convert to fraction form
    420.76/581.34 = 321.54/x
  3. Step 3: Cross multiply
    420.76x = 581.34 × 321.54
  4. Step 4: Simplify right side
    420.76x = 186,924.06
  5. Step 5: Solve for x
    x = 186,924.06/420.76
  6. Step 6: Final answer
    x = 444.25

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Find fourth proportional to 210.38, 290.67 and 160.77
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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.