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Finding the Fourth Proportional to 79.48, 119.20 and 78.81

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Solution

The fourth proportional to 79.48, 119.20 and 78.81 is: 118.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.48 : 119.20 = 78.81 : x
  2. Step 2: Convert to fraction form
    79.48/119.20 = 78.81/x
  3. Step 3: Cross multiply
    79.48x = 119.20 × 78.81
  4. Step 4: Simplify right side
    79.48x = 9,394.15
  5. Step 5: Solve for x
    x = 9,394.15/79.48
  6. Step 6: Final answer
    x = 118.20

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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.