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Finding the Fourth Proportional to 79.56, 109.56 and 65.76

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Solution

The fourth proportional to 79.56, 109.56 and 65.76 is: 90.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.56 : 109.56 = 65.76 : x
  2. Step 2: Convert to fraction form
    79.56/109.56 = 65.76/x
  3. Step 3: Cross multiply
    79.56x = 109.56 × 65.76
  4. Step 4: Simplify right side
    79.56x = 7,204.67
  5. Step 5: Solve for x
    x = 7,204.67/79.56
  6. Step 6: Final answer
    x = 90.56

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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.