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Finding the Fourth Proportional to 5.00, 7.50 and 3.80

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Solution

The fourth proportional to 5.00, 7.50 and 3.80 is: 5.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.00 : 7.50 = 3.80 : x
  2. Step 2: Convert to fraction form
    5.00/7.50 = 3.80/x
  3. Step 3: Cross multiply
    5.00x = 7.50 × 3.80
  4. Step 4: Simplify right side
    5.00x = 28.50
  5. Step 5: Solve for x
    x = 28.50/5.00
  6. Step 6: Final answer
    x = 5.70

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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.