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Finding the Fourth Proportional to 711.29, 981.20 and 490.35

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Solution

The fourth proportional to 711.29, 981.20 and 490.35 is: 676.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.29 : 981.20 = 490.35 : x
  2. Step 2: Convert to fraction form
    711.29/981.20 = 490.35/x
  3. Step 3: Cross multiply
    711.29x = 981.20 × 490.35
  4. Step 4: Simplify right side
    711.29x = 481,128.97
  5. Step 5: Solve for x
    x = 481,128.97/711.29
  6. Step 6: Final answer
    x = 676.42

Related Problems

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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.