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Finding the Fourth Proportional to 684.78, 945 and 422.76

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Solution

The fourth proportional to 684.78, 945 and 422.76 is: 583.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.78 : 945 = 422.76 : x
  2. Step 2: Convert to fraction form
    684.78/945 = 422.76/x
  3. Step 3: Cross multiply
    684.78x = 945 × 422.76
  4. Step 4: Simplify right side
    684.78x = 399,508.20
  5. Step 5: Solve for x
    x = 399,508.20/684.78
  6. Step 6: Final answer
    x = 583.41

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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.