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Finding the Fourth Proportional to 20.60, 28.30 and 18.28

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Solution

The fourth proportional to 20.60, 28.30 and 18.28 is: 25.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.60 : 28.30 = 18.28 : x
  2. Step 2: Convert to fraction form
    20.60/28.30 = 18.28/x
  3. Step 3: Cross multiply
    20.60x = 28.30 × 18.28
  4. Step 4: Simplify right side
    20.60x = 517.19
  5. Step 5: Solve for x
    x = 517.19/20.60
  6. Step 6: Final answer
    x = 25.10

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.