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Finding the Fourth Proportional to 2.16, 3.20 and 2.15

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Solution

The fourth proportional to 2.16, 3.20 and 2.15 is: 3.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.16 : 3.20 = 2.15 : x
  2. Step 2: Convert to fraction form
    2.16/3.20 = 2.15/x
  3. Step 3: Cross multiply
    2.16x = 3.20 × 2.15
  4. Step 4: Simplify right side
    2.16x = 6.87
  5. Step 5: Solve for x
    x = 6.87/2.16
  6. Step 6: Final answer
    x = 3.18

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.