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Finding the Fourth Proportional to 3.21, 4.80 and 1.87

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Solution

The fourth proportional to 3.21, 4.80 and 1.87 is: 2.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.21 : 4.80 = 1.87 : x
  2. Step 2: Convert to fraction form
    3.21/4.80 = 1.87/x
  3. Step 3: Cross multiply
    3.21x = 4.80 × 1.87
  4. Step 4: Simplify right side
    3.21x = 8.98
  5. Step 5: Solve for x
    x = 8.98/3.21
  6. Step 6: Final answer
    x = 2.80

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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.