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Finding the Fourth Proportional to 51.25, 76.80 and 28.10

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Solution

The fourth proportional to 51.25, 76.80 and 28.10 is: 42.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.25 : 76.80 = 28.10 : x
  2. Step 2: Convert to fraction form
    51.25/76.80 = 28.10/x
  3. Step 3: Cross multiply
    51.25x = 76.80 × 28.10
  4. Step 4: Simplify right side
    51.25x = 2,158.08
  5. Step 5: Solve for x
    x = 2,158.08/51.25
  6. Step 6: Final answer
    x = 42.11

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.