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Finding the Fourth Proportional to 390.43, 538.16 and 320.37

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Solution

The fourth proportional to 390.43, 538.16 and 320.37 is: 441.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.43 : 538.16 = 320.37 : x
  2. Step 2: Convert to fraction form
    390.43/538.16 = 320.37/x
  3. Step 3: Cross multiply
    390.43x = 538.16 × 320.37
  4. Step 4: Simplify right side
    390.43x = 172,410.32
  5. Step 5: Solve for x
    x = 172,410.32/390.43
  6. Step 6: Final answer
    x = 441.59

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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.