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Finding the Fourth Proportional to 9.70, 12.80 and 9.70

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Solution

The fourth proportional to 9.70, 12.80 and 9.70 is: 12.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    9.70 : 12.80 = 9.70 : x
  2. Step 2: Convert to fraction form
    9.70/12.80 = 9.70/x
  3. Step 3: Cross multiply
    9.70x = 12.80 × 9.70
  4. Step 4: Simplify right side
    9.70x = 124.16
  5. Step 5: Solve for x
    x = 124.16/9.70
  6. Step 6: Final answer
    x = 12.80

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Why These Related Problems?

These problems maintain the same ratio (1.32) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.