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Finding the Fourth Proportional to 390.33, 585.51 and 130.21

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Solution

The fourth proportional to 390.33, 585.51 and 130.21 is: 195.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.33 : 585.51 = 130.21 : x
  2. Step 2: Convert to fraction form
    390.33/585.51 = 130.21/x
  3. Step 3: Cross multiply
    390.33x = 585.51 × 130.21
  4. Step 4: Simplify right side
    390.33x = 76,239.26
  5. Step 5: Solve for x
    x = 76,239.26/390.33
  6. Step 6: Final answer
    x = 195.32

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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.