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Finding the Fourth Proportional to 4.80, 7.15 and 4.28

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Solution

The fourth proportional to 4.80, 7.15 and 4.28 is: 6.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.80 : 7.15 = 4.28 : x
  2. Step 2: Convert to fraction form
    4.80/7.15 = 4.28/x
  3. Step 3: Cross multiply
    4.80x = 7.15 × 4.28
  4. Step 4: Simplify right side
    4.80x = 30.60
  5. Step 5: Solve for x
    x = 30.60/4.80
  6. Step 6: Final answer
    x = 6.38

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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.