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Finding the Fourth Proportional to 389.00, 582.58 and 215.39

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Solution

The fourth proportional to 389.00, 582.58 and 215.39 is: 322.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.00 : 582.58 = 215.39 : x
  2. Step 2: Convert to fraction form
    389.00/582.58 = 215.39/x
  3. Step 3: Cross multiply
    389.00x = 582.58 × 215.39
  4. Step 4: Simplify right side
    389.00x = 125,479.26
  5. Step 5: Solve for x
    x = 125,479.26/389.00
  6. Step 6: Final answer
    x = 322.57

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.