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Finding the Fourth Proportional to 20.16, 27.78 and 15.30

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Solution

The fourth proportional to 20.16, 27.78 and 15.30 is: 21.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.16 : 27.78 = 15.30 : x
  2. Step 2: Convert to fraction form
    20.16/27.78 = 15.30/x
  3. Step 3: Cross multiply
    20.16x = 27.78 × 15.30
  4. Step 4: Simplify right side
    20.16x = 425.03
  5. Step 5: Solve for x
    x = 425.03/20.16
  6. Step 6: Final answer
    x = 21.08

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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.