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Finding the Fourth Proportional to 25.87, 35.65 and 20.40

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Solution

The fourth proportional to 25.87, 35.65 and 20.40 is: 28.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.87 : 35.65 = 20.40 : x
  2. Step 2: Convert to fraction form
    25.87/35.65 = 20.40/x
  3. Step 3: Cross multiply
    25.87x = 35.65 × 20.40
  4. Step 4: Simplify right side
    25.87x = 727.21
  5. Step 5: Solve for x
    x = 727.21/25.87
  6. Step 6: Final answer
    x = 28.11

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.