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Finding the Fourth Proportional to 717.55, 990.17 and 402.76

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Solution

The fourth proportional to 717.55, 990.17 and 402.76 is: 555.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.55 : 990.17 = 402.76 : x
  2. Step 2: Convert to fraction form
    717.55/990.17 = 402.76/x
  3. Step 3: Cross multiply
    717.55x = 990.17 × 402.76
  4. Step 4: Simplify right side
    717.55x = 398,800.87
  5. Step 5: Solve for x
    x = 398,800.87/717.55
  6. Step 6: Final answer
    x = 555.78

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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.