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Finding the Fourth Proportional to 79.60, 109.81 and 62.18

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Solution

The fourth proportional to 79.60, 109.81 and 62.18 is: 85.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.60 : 109.81 = 62.18 : x
  2. Step 2: Convert to fraction form
    79.60/109.81 = 62.18/x
  3. Step 3: Cross multiply
    79.60x = 109.81 × 62.18
  4. Step 4: Simplify right side
    79.60x = 6,827.99
  5. Step 5: Solve for x
    x = 6,827.99/79.60
  6. Step 6: Final answer
    x = 85.78

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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.