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Finding the Fourth Proportional to 30.05, 41.43 and 21.87

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Solution

The fourth proportional to 30.05, 41.43 and 21.87 is: 30.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.05 : 41.43 = 21.87 : x
  2. Step 2: Convert to fraction form
    30.05/41.43 = 21.87/x
  3. Step 3: Cross multiply
    30.05x = 41.43 × 21.87
  4. Step 4: Simplify right side
    30.05x = 906.07
  5. Step 5: Solve for x
    x = 906.07/30.05
  6. Step 6: Final answer
    x = 30.16

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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.