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Finding the Fourth Proportional to 20.85, 28.69 and 19

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Solution

The fourth proportional to 20.85, 28.69 and 19 is: 26.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.85 : 28.69 = 19 : x
  2. Step 2: Convert to fraction form
    20.85/28.69 = 19/x
  3. Step 3: Cross multiply
    20.85x = 28.69 × 19
  4. Step 4: Simplify right side
    20.85x = 545.11
  5. Step 5: Solve for x
    x = 545.11/20.85
  6. Step 6: Final answer
    x = 26.14

Related Problems

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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.