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Finding the Third Proportional to 4 and 5

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Solution

The third proportional to 4 and 5 is: 6.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    4 : 5 = 5 : x
  2. Step 2: Convert to fraction form
    4/5 = 5/x
  3. Step 3: Cross multiply
    4x = 5 × 5
  4. Step 4: Simplify right side
    4x = 25
  5. Step 5: Solve for x
    x = 25/4
  6. Step 6: Final answer
    x = 6.25

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Why These Related Problems?

These problems maintain the same ratio (1.25) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.