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Finding the Fourth Proportional to 420.22, 631.41 and 380.26

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Solution

The fourth proportional to 420.22, 631.41 and 380.26 is: 571.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.22 : 631.41 = 380.26 : x
  2. Step 2: Convert to fraction form
    420.22/631.41 = 380.26/x
  3. Step 3: Cross multiply
    420.22x = 631.41 × 380.26
  4. Step 4: Simplify right side
    420.22x = 240,099.97
  5. Step 5: Solve for x
    x = 240,099.97/420.22
  6. Step 6: Final answer
    x = 571.37

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Double scale
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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.