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Finding the Fourth Proportional to 685.28, 945.68 and 374.78

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Solution

The fourth proportional to 685.28, 945.68 and 374.78 is: 517.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.28 : 945.68 = 374.78 : x
  2. Step 2: Convert to fraction form
    685.28/945.68 = 374.78/x
  3. Step 3: Cross multiply
    685.28x = 945.68 × 374.78
  4. Step 4: Simplify right side
    685.28x = 354,417.22
  5. Step 5: Solve for x
    x = 354,417.22/685.28
  6. Step 6: Final answer
    x = 517.19

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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.