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Finding the Fourth Proportional to 288.81, 398.32 and 217.60

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Solution

The fourth proportional to 288.81, 398.32 and 217.60 is: 300.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.81 : 398.32 = 217.60 : x
  2. Step 2: Convert to fraction form
    288.81/398.32 = 217.60/x
  3. Step 3: Cross multiply
    288.81x = 398.32 × 217.60
  4. Step 4: Simplify right side
    288.81x = 86,672.89
  5. Step 5: Solve for x
    x = 86,672.89/288.81
  6. Step 6: Final answer
    x = 300.10

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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.