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Finding the Fourth Proportional to 290.81, 401.63 and 288.79

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Solution

The fourth proportional to 290.81, 401.63 and 288.79 is: 398.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.81 : 401.63 = 288.79 : x
  2. Step 2: Convert to fraction form
    290.81/401.63 = 288.79/x
  3. Step 3: Cross multiply
    290.81x = 401.63 × 288.79
  4. Step 4: Simplify right side
    290.81x = 115,984.28
  5. Step 5: Solve for x
    x = 115,984.28/290.81
  6. Step 6: Final answer
    x = 398.83

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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.