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Finding the Fourth Proportional to 30, 41.38 and 19.64

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Solution

The fourth proportional to 30, 41.38 and 19.64 is: 27.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    30 : 41.38 = 19.64 : x
  2. Step 2: Convert to fraction form
    30/41.38 = 19.64/x
  3. Step 3: Cross multiply
    30x = 41.38 × 19.64
  4. Step 4: Simplify right side
    30x = 812.70
  5. Step 5: Solve for x
    x = 812.70/30
  6. Step 6: Final answer
    x = 27.09

Related Problems

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Double scale
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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.