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Finding the Third Proportional to 100 and 130

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Solution

The third proportional to 100 and 130 is: 169

Step by Step Solution

  1. Step 1: Write the proportion equation
    100 : 130 = 130 : x
  2. Step 2: Convert to fraction form
    100/130 = 130/x
  3. Step 3: Cross multiply
    100x = 130 × 130
  4. Step 4: Simplify right side
    100x = 16,900
  5. Step 5: Solve for x
    x = 16,900/100
  6. Step 6: Final answer
    x = 169

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.