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Finding the Fourth Proportional to 287.65, 397.31 and 225.69

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Solution

The fourth proportional to 287.65, 397.31 and 225.69 is: 311.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.65 : 397.31 = 225.69 : x
  2. Step 2: Convert to fraction form
    287.65/397.31 = 225.69/x
  3. Step 3: Cross multiply
    287.65x = 397.31 × 225.69
  4. Step 4: Simplify right side
    287.65x = 89,666.28
  5. Step 5: Solve for x
    x = 89,666.28/287.65
  6. Step 6: Final answer
    x = 311.72

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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.