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Finding the Fourth Proportional to 911.39, 1,257.53 and 579.70

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Solution

The fourth proportional to 911.39, 1,257.53 and 579.70 is: 799.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    911.39 : 1,257.53 = 579.70 : x
  2. Step 2: Convert to fraction form
    911.39/1,257.53 = 579.70/x
  3. Step 3: Cross multiply
    911.39x = 1,257.53 × 579.70
  4. Step 4: Simplify right side
    911.39x = 728,990.14
  5. Step 5: Solve for x
    x = 728,990.14/911.39
  6. Step 6: Final answer
    x = 799.87

Related Problems

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Half scale
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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.