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Finding the Fourth Proportional to 19.30, 28.90 and 15

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Solution

The fourth proportional to 19.30, 28.90 and 15 is: 22.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.30 : 28.90 = 15 : x
  2. Step 2: Convert to fraction form
    19.30/28.90 = 15/x
  3. Step 3: Cross multiply
    19.30x = 28.90 × 15
  4. Step 4: Simplify right side
    19.30x = 433.50
  5. Step 5: Solve for x
    x = 433.50/19.30
  6. Step 6: Final answer
    x = 22.46

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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.