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Finding the Fourth Proportional to 27.87, 38.40 and 18.15

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Solution

The fourth proportional to 27.87, 38.40 and 18.15 is: 25.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    27.87 : 38.40 = 18.15 : x
  2. Step 2: Convert to fraction form
    27.87/38.40 = 18.15/x
  3. Step 3: Cross multiply
    27.87x = 38.40 × 18.15
  4. Step 4: Simplify right side
    27.87x = 696.96
  5. Step 5: Solve for x
    x = 696.96/27.87
  6. Step 6: Final answer
    x = 25.01

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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.