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Finding the Fourth Proportional to 28.69, 42.80 and 28.49

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Solution

The fourth proportional to 28.69, 42.80 and 28.49 is: 42.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.69 : 42.80 = 28.49 : x
  2. Step 2: Convert to fraction form
    28.69/42.80 = 28.49/x
  3. Step 3: Cross multiply
    28.69x = 42.80 × 28.49
  4. Step 4: Simplify right side
    28.69x = 1,219.37
  5. Step 5: Solve for x
    x = 1,219.37/28.69
  6. Step 6: Final answer
    x = 42.50

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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.