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Finding the Fourth Proportional to 711.18, 981.42 and 490.15

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Solution

The fourth proportional to 711.18, 981.42 and 490.15 is: 676.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.18 : 981.42 = 490.15 : x
  2. Step 2: Convert to fraction form
    711.18/981.42 = 490.15/x
  3. Step 3: Cross multiply
    711.18x = 981.42 × 490.15
  4. Step 4: Simplify right side
    711.18x = 481,042.40
  5. Step 5: Solve for x
    x = 481,042.40/711.18
  6. Step 6: Final answer
    x = 676.40

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.