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Finding the Fourth Proportional to 399.37, 551.32 and 320.55

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Solution

The fourth proportional to 399.37, 551.32 and 320.55 is: 442.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.37 : 551.32 = 320.55 : x
  2. Step 2: Convert to fraction form
    399.37/551.32 = 320.55/x
  3. Step 3: Cross multiply
    399.37x = 551.32 × 320.55
  4. Step 4: Simplify right side
    399.37x = 176,725.63
  5. Step 5: Solve for x
    x = 176,725.63/399.37
  6. Step 6: Final answer
    x = 442.51

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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.