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Finding the Fourth Proportional to 668.13, 920.55 and 499.38

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Solution

The fourth proportional to 668.13, 920.55 and 499.38 is: 688.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.13 : 920.55 = 499.38 : x
  2. Step 2: Convert to fraction form
    668.13/920.55 = 499.38/x
  3. Step 3: Cross multiply
    668.13x = 920.55 × 499.38
  4. Step 4: Simplify right side
    668.13x = 459,704.26
  5. Step 5: Solve for x
    x = 459,704.26/668.13
  6. Step 6: Final answer
    x = 688.05

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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.