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Finding the Fourth Proportional to 7.50, 10.40 and 7.28

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Solution

The fourth proportional to 7.50, 10.40 and 7.28 is: 10.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.50 : 10.40 = 7.28 : x
  2. Step 2: Convert to fraction form
    7.50/10.40 = 7.28/x
  3. Step 3: Cross multiply
    7.50x = 10.40 × 7.28
  4. Step 4: Simplify right side
    7.50x = 75.71
  5. Step 5: Solve for x
    x = 75.71/7.50
  6. Step 6: Final answer
    x = 10.09

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.