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Finding the Fourth Proportional to 20.30, 28 and 12.53

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Solution

The fourth proportional to 20.30, 28 and 12.53 is: 17.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.30 : 28 = 12.53 : x
  2. Step 2: Convert to fraction form
    20.30/28 = 12.53/x
  3. Step 3: Cross multiply
    20.30x = 28 × 12.53
  4. Step 4: Simplify right side
    20.30x = 350.84
  5. Step 5: Solve for x
    x = 350.84/20.30
  6. Step 6: Final answer
    x = 17.28

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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.