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Finding the Fourth Proportional to 387.38, 534.80 and 289.37

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Solution

The fourth proportional to 387.38, 534.80 and 289.37 is: 399.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.38 : 534.80 = 289.37 : x
  2. Step 2: Convert to fraction form
    387.38/534.80 = 289.37/x
  3. Step 3: Cross multiply
    387.38x = 534.80 × 289.37
  4. Step 4: Simplify right side
    387.38x = 154,755.08
  5. Step 5: Solve for x
    x = 154,755.08/387.38
  6. Step 6: Final answer
    x = 399.49

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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.