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Finding the Fourth Proportional to 712.24, 981.78 and 490.70

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Solution

The fourth proportional to 712.24, 981.78 and 490.70 is: 676.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.24 : 981.78 = 490.70 : x
  2. Step 2: Convert to fraction form
    712.24/981.78 = 490.70/x
  3. Step 3: Cross multiply
    712.24x = 981.78 × 490.70
  4. Step 4: Simplify right side
    712.24x = 481,759.45
  5. Step 5: Solve for x
    x = 481,759.45/712.24
  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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Similar ratio
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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.