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Finding the Fourth Proportional to 287.85, 397.10 and 189.60

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Solution

The fourth proportional to 287.85, 397.10 and 189.60 is: 261.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.85 : 397.10 = 189.60 : x
  2. Step 2: Convert to fraction form
    287.85/397.10 = 189.60/x
  3. Step 3: Cross multiply
    287.85x = 397.10 × 189.60
  4. Step 4: Simplify right side
    287.85x = 75,289.21
  5. Step 5: Solve for x
    x = 75,289.21/287.85
  6. Step 6: Final answer
    x = 261.56

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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.