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Finding the Fourth Proportional to 30.45, 45.42 and 28.44

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Solution

The fourth proportional to 30.45, 45.42 and 28.44 is: 42.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.45 : 45.42 = 28.44 : x
  2. Step 2: Convert to fraction form
    30.45/45.42 = 28.44/x
  3. Step 3: Cross multiply
    30.45x = 45.42 × 28.44
  4. Step 4: Simplify right side
    30.45x = 1,291.74
  5. Step 5: Solve for x
    x = 1,291.74/30.45
  6. Step 6: Final answer
    x = 42.42

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.