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Finding the Fourth Proportional to 420.09, 627.73 and 320.71

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Solution

The fourth proportional to 420.09, 627.73 and 320.71 is: 479.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.09 : 627.73 = 320.71 : x
  2. Step 2: Convert to fraction form
    420.09/627.73 = 320.71/x
  3. Step 3: Cross multiply
    420.09x = 627.73 × 320.71
  4. Step 4: Simplify right side
    420.09x = 201,317.68
  5. Step 5: Solve for x
    x = 201,317.68/420.09
  6. Step 6: Final answer
    x = 479.23

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.