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Finding the Fourth Proportional to 389.65, 581.61 and 343.51

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Solution

The fourth proportional to 389.65, 581.61 and 343.51 is: 512.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.65 : 581.61 = 343.51 : x
  2. Step 2: Convert to fraction form
    389.65/581.61 = 343.51/x
  3. Step 3: Cross multiply
    389.65x = 581.61 × 343.51
  4. Step 4: Simplify right side
    389.65x = 199,789.71
  5. Step 5: Solve for x
    x = 199,789.71/389.65
  6. Step 6: Final answer
    x = 512.75

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.