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Finding the Fourth Proportional to 660.19, 911.10 and 398.29

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Solution

The fourth proportional to 660.19, 911.10 and 398.29 is: 549.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.19 : 911.10 = 398.29 : x
  2. Step 2: Convert to fraction form
    660.19/911.10 = 398.29/x
  3. Step 3: Cross multiply
    660.19x = 911.10 × 398.29
  4. Step 4: Simplify right side
    660.19x = 362,882.02
  5. Step 5: Solve for x
    x = 362,882.02/660.19
  6. Step 6: Final answer
    x = 549.66

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