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Finding the Fourth Proportional to 84.79, 127.20 and 39.13

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Solution

The fourth proportional to 84.79, 127.20 and 39.13 is: 58.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.79 : 127.20 = 39.13 : x
  2. Step 2: Convert to fraction form
    84.79/127.20 = 39.13/x
  3. Step 3: Cross multiply
    84.79x = 127.20 × 39.13
  4. Step 4: Simplify right side
    84.79x = 4,976.50
  5. Step 5: Solve for x
    x = 4,976.50/84.79
  6. Step 6: Final answer
    x = 58.69

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Double scale
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Similar ratio
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1.5x scale

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.