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Finding the Fourth Proportional to 387.47, 533.79 and 320.81

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Solution

The fourth proportional to 387.47, 533.79 and 320.81 is: 441.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.47 : 533.79 = 320.81 : x
  2. Step 2: Convert to fraction form
    387.47/533.79 = 320.81/x
  3. Step 3: Cross multiply
    387.47x = 533.79 × 320.81
  4. Step 4: Simplify right side
    387.47x = 171,242.50
  5. Step 5: Solve for x
    x = 171,242.50/387.47
  6. Step 6: Final answer
    x = 441.96

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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.