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Finding the Fourth Proportional to 3.20, 4.80 and 1.20

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Solution

The fourth proportional to 3.20, 4.80 and 1.20 is: 1.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.20 : 4.80 = 1.20 : x
  2. Step 2: Convert to fraction form
    3.20/4.80 = 1.20/x
  3. Step 3: Cross multiply
    3.20x = 4.80 × 1.20
  4. Step 4: Simplify right side
    3.20x = 5.75
  5. Step 5: Solve for x
    x = 5.75/3.20
  6. Step 6: Final answer
    x = 1.80

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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.