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Finding the Fourth Proportional to 865.91, 1,298.89 and 288.79

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Solution

The fourth proportional to 865.91, 1,298.89 and 288.79 is: 433.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.91 : 1,298.89 = 288.79 : x
  2. Step 2: Convert to fraction form
    865.91/1,298.89 = 288.79/x
  3. Step 3: Cross multiply
    865.91x = 1,298.89 × 288.79
  4. Step 4: Simplify right side
    865.91x = 375,098.50
  5. Step 5: Solve for x
    x = 375,098.50/865.91
  6. Step 6: Final answer
    x = 433.18

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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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.