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Finding the Fourth Proportional to 390.28, 585.50 and 130.30

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Solution

The fourth proportional to 390.28, 585.50 and 130.30 is: 195.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.28 : 585.50 = 130.30 : x
  2. Step 2: Convert to fraction form
    390.28/585.50 = 130.30/x
  3. Step 3: Cross multiply
    390.28x = 585.50 × 130.30
  4. Step 4: Simplify right side
    390.28x = 76,290.65
  5. Step 5: Solve for x
    x = 76,290.65/390.28
  6. Step 6: Final answer
    x = 195.48

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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.