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Finding the Fourth Proportional to 79.14, 109.15 and 63.57

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Solution

The fourth proportional to 79.14, 109.15 and 63.57 is: 87.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.14 : 109.15 = 63.57 : x
  2. Step 2: Convert to fraction form
    79.14/109.15 = 63.57/x
  3. Step 3: Cross multiply
    79.14x = 109.15 × 63.57
  4. Step 4: Simplify right side
    79.14x = 6,938.67
  5. Step 5: Solve for x
    x = 6,938.67/79.14
  6. Step 6: Final answer
    x = 87.68

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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.