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Finding the Fourth Proportional to 20.15, 30.19 and 10.51

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Solution

The fourth proportional to 20.15, 30.19 and 10.51 is: 15.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.15 : 30.19 = 10.51 : x
  2. Step 2: Convert to fraction form
    20.15/30.19 = 10.51/x
  3. Step 3: Cross multiply
    20.15x = 30.19 × 10.51
  4. Step 4: Simplify right side
    20.15x = 317.30
  5. Step 5: Solve for x
    x = 317.30/20.15
  6. Step 6: Final answer
    x = 15.75

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1.5x scale

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.