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Finding the Fourth Proportional to 5.25, 7.78 and 5.20

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Solution

The fourth proportional to 5.25, 7.78 and 5.20 is: 7.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.25 : 7.78 = 5.20 : x
  2. Step 2: Convert to fraction form
    5.25/7.78 = 5.20/x
  3. Step 3: Cross multiply
    5.25x = 7.78 × 5.20
  4. Step 4: Simplify right side
    5.25x = 40.46
  5. Step 5: Solve for x
    x = 40.46/5.25
  6. Step 6: Final answer
    x = 7.71

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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.