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Finding the Fourth Proportional to 7.28, 10.05 and 4.05

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Solution

The fourth proportional to 7.28, 10.05 and 4.05 is: 5.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.28 : 10.05 = 4.05 : x
  2. Step 2: Convert to fraction form
    7.28/10.05 = 4.05/x
  3. Step 3: Cross multiply
    7.28x = 10.05 × 4.05
  4. Step 4: Simplify right side
    7.28x = 40.66
  5. Step 5: Solve for x
    x = 40.66/7.28
  6. Step 6: Final answer
    x = 5.58

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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.