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Finding the Fourth Proportional to 30.17, 45.15 and 20.51

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Solution

The fourth proportional to 30.17, 45.15 and 20.51 is: 30.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.17 : 45.15 = 20.51 : x
  2. Step 2: Convert to fraction form
    30.17/45.15 = 20.51/x
  3. Step 3: Cross multiply
    30.17x = 45.15 × 20.51
  4. Step 4: Simplify right side
    30.17x = 925.80
  5. Step 5: Solve for x
    x = 925.80/30.17
  6. Step 6: Final answer
    x = 30.69

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.