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Finding the Fourth Proportional to 260.42, 390.20 and 199.40

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Solution

The fourth proportional to 260.42, 390.20 and 199.40 is: 298.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    260.42 : 390.20 = 199.40 : x
  2. Step 2: Convert to fraction form
    260.42/390.20 = 199.40/x
  3. Step 3: Cross multiply
    260.42x = 390.20 × 199.40
  4. Step 4: Simplify right side
    260.42x = 77,805.88
  5. Step 5: Solve for x
    x = 77,805.88/260.42
  6. Step 6: Final answer
    x = 298.77

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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.