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Finding the Fourth Proportional to 30, 41.38 and 20.17

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Solution

The fourth proportional to 30, 41.38 and 20.17 is: 27.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    30 : 41.38 = 20.17 : x
  2. Step 2: Convert to fraction form
    30/41.38 = 20.17/x
  3. Step 3: Cross multiply
    30x = 41.38 × 20.17
  4. Step 4: Simplify right side
    30x = 834.48
  5. Step 5: Solve for x
    x = 834.48/30
  6. Step 6: Final answer
    x = 27.82

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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.