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Finding the Fourth Proportional to 25.65, 38.25 and 20.55

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Solution

The fourth proportional to 25.65, 38.25 and 20.55 is: 30.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.65 : 38.25 = 20.55 : x
  2. Step 2: Convert to fraction form
    25.65/38.25 = 20.55/x
  3. Step 3: Cross multiply
    25.65x = 38.25 × 20.55
  4. Step 4: Simplify right side
    25.65x = 786.04
  5. Step 5: Solve for x
    x = 786.04/25.65
  6. Step 6: Final answer
    x = 30.64

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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.