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Finding the Fourth Proportional to 386.99, 534.12 and 239.69

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Solution

The fourth proportional to 386.99, 534.12 and 239.69 is: 330.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.99 : 534.12 = 239.69 : x
  2. Step 2: Convert to fraction form
    386.99/534.12 = 239.69/x
  3. Step 3: Cross multiply
    386.99x = 534.12 × 239.69
  4. Step 4: Simplify right side
    386.99x = 128,019.35
  5. Step 5: Solve for x
    x = 128,019.35/386.99
  6. Step 6: Final answer
    x = 330.81

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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.