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Finding the Fourth Proportional to 71.69, 107.28 and 64.20

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Solution

The fourth proportional to 71.69, 107.28 and 64.20 is: 96.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.69 : 107.28 = 64.20 : x
  2. Step 2: Convert to fraction form
    71.69/107.28 = 64.20/x
  3. Step 3: Cross multiply
    71.69x = 107.28 × 64.20
  4. Step 4: Simplify right side
    71.69x = 6,887.38
  5. Step 5: Solve for x
    x = 6,887.38/71.69
  6. Step 6: Final answer
    x = 96.07

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.