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Finding the Fourth Proportional to 338.90, 509.01 and 320.51

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Solution

The fourth proportional to 338.90, 509.01 and 320.51 is: 481.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.90 : 509.01 = 320.51 : x
  2. Step 2: Convert to fraction form
    338.90/509.01 = 320.51/x
  3. Step 3: Cross multiply
    338.90x = 509.01 × 320.51
  4. Step 4: Simplify right side
    338.90x = 163,140.25
  5. Step 5: Solve for x
    x = 163,140.25/338.90
  6. Step 6: Final answer
    x = 481.39

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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.