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Finding the Fourth Proportional to 2.16, 3.22 and 1.78

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Solution

The fourth proportional to 2.16, 3.22 and 1.78 is: 2.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.16 : 3.22 = 1.78 : x
  2. Step 2: Convert to fraction form
    2.16/3.22 = 1.78/x
  3. Step 3: Cross multiply
    2.16x = 3.22 × 1.78
  4. Step 4: Simplify right side
    2.16x = 5.73
  5. Step 5: Solve for x
    x = 5.73/2.16
  6. Step 6: Final answer
    x = 2.65

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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.