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Finding the Fourth Proportional to 79.82, 119.90 and 49.40

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Solution

The fourth proportional to 79.82, 119.90 and 49.40 is: 74.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.82 : 119.90 = 49.40 : x
  2. Step 2: Convert to fraction form
    79.82/119.90 = 49.40/x
  3. Step 3: Cross multiply
    79.82x = 119.90 × 49.40
  4. Step 4: Simplify right side
    79.82x = 5,922.21
  5. Step 5: Solve for x
    x = 5,922.21/79.82
  6. Step 6: Final answer
    x = 74.20

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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.