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Finding the Fourth Proportional to 28.99, 39.89 and 25.55

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Solution

The fourth proportional to 28.99, 39.89 and 25.55 is: 35.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.99 : 39.89 = 25.55 : x
  2. Step 2: Convert to fraction form
    28.99/39.89 = 25.55/x
  3. Step 3: Cross multiply
    28.99x = 39.89 × 25.55
  4. Step 4: Simplify right side
    28.99x = 1,018.86
  5. Step 5: Solve for x
    x = 1,018.86/28.99
  6. Step 6: Final answer
    x = 35.15

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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.