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Finding the Fourth Proportional to 287.64, 397.07 and 217.71

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Solution

The fourth proportional to 287.64, 397.07 and 217.71 is: 300.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.64 : 397.07 = 217.71 : x
  2. Step 2: Convert to fraction form
    287.64/397.07 = 217.71/x
  3. Step 3: Cross multiply
    287.64x = 397.07 × 217.71
  4. Step 4: Simplify right side
    287.64x = 86,445.02
  5. Step 5: Solve for x
    x = 86,445.02/287.64
  6. Step 6: Final answer
    x = 300.53

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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.