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Finding the Fourth Proportional to 8.71, 12 and 6.89

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Solution

The fourth proportional to 8.71, 12 and 6.89 is: 9.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.71 : 12 = 6.89 : x
  2. Step 2: Convert to fraction form
    8.71/12 = 6.89/x
  3. Step 3: Cross multiply
    8.71x = 12 × 6.89
  4. Step 4: Simplify right side
    8.71x = 82.68
  5. Step 5: Solve for x
    x = 82.68/8.71
  6. Step 6: Final answer
    x = 9.49

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1.5x scale

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.