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Finding the Fourth Proportional to 3.45, 5.21 and 3.40

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Solution

The fourth proportional to 3.45, 5.21 and 3.40 is: 5.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.45 : 5.21 = 3.40 : x
  2. Step 2: Convert to fraction form
    3.45/5.21 = 3.40/x
  3. Step 3: Cross multiply
    3.45x = 5.21 × 3.40
  4. Step 4: Simplify right side
    3.45x = 17.70
  5. Step 5: Solve for x
    x = 17.70/3.45
  6. Step 6: Final answer
    x = 5.12

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.