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Finding the Third Proportional to 4.20 and 8.45

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Solution

The third proportional to 4.20 and 8.45 is: 17.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.20 : 8.45 = 8.45 : x
  2. Step 2: Convert to fraction form
    4.20/8.45 = 8.45/x
  3. Step 3: Cross multiply
    4.20x = 8.45 × 8.45
  4. Step 4: Simplify right side
    4.20x = 71.45
  5. Step 5: Solve for x
    x = 71.45/4.20
  6. Step 6: Final answer
    x = 17.01

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.01) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.