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Finding the Fourth Proportional to 638.40, 957.60 and 205.66

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Solution

The fourth proportional to 638.40, 957.60 and 205.66 is: 308.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.40 : 957.60 = 205.66 : x
  2. Step 2: Convert to fraction form
    638.40/957.60 = 205.66/x
  3. Step 3: Cross multiply
    638.40x = 957.60 × 205.66
  4. Step 4: Simplify right side
    638.40x = 196,940.02
  5. Step 5: Solve for x
    x = 196,940.02/638.40
  6. Step 6: Final answer
    x = 308.49

Related Problems

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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.