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Finding the Fourth Proportional to 73.20, 109.20 and 64.20

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Solution

The fourth proportional to 73.20, 109.20 and 64.20 is: 95.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    73.20 : 109.20 = 64.20 : x
  2. Step 2: Convert to fraction form
    73.20/109.20 = 64.20/x
  3. Step 3: Cross multiply
    73.20x = 109.20 × 64.20
  4. Step 4: Simplify right side
    73.20x = 7,010.64
  5. Step 5: Solve for x
    x = 7,010.64/73.20
  6. Step 6: Final answer
    x = 95.77

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.