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Finding the Fourth Proportional to 666.68, 920.11 and 480.78

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Solution

The fourth proportional to 666.68, 920.11 and 480.78 is: 663.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.68 : 920.11 = 480.78 : x
  2. Step 2: Convert to fraction form
    666.68/920.11 = 480.78/x
  3. Step 3: Cross multiply
    666.68x = 920.11 × 480.78
  4. Step 4: Simplify right side
    666.68x = 442,370.49
  5. Step 5: Solve for x
    x = 442,370.49/666.68
  6. Step 6: Final answer
    x = 663.54

Related Problems

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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.