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Finding the Fourth Proportional to 653.20, 979.78 and 220.32

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Solution

The fourth proportional to 653.20, 979.78 and 220.32 is: 330.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.20 : 979.78 = 220.32 : x
  2. Step 2: Convert to fraction form
    653.20/979.78 = 220.32/x
  3. Step 3: Cross multiply
    653.20x = 979.78 × 220.32
  4. Step 4: Simplify right side
    653.20x = 215,865.13
  5. Step 5: Solve for x
    x = 215,865.13/653.20
  6. Step 6: Final answer
    x = 330.47

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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.