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Finding the Fourth Proportional to 390.18, 585.40 and 159.10

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Solution

The fourth proportional to 390.18, 585.40 and 159.10 is: 238.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.18 : 585.40 = 159.10 : x
  2. Step 2: Convert to fraction form
    390.18/585.40 = 159.10/x
  3. Step 3: Cross multiply
    390.18x = 585.40 × 159.10
  4. Step 4: Simplify right side
    390.18x = 93,137.14
  5. Step 5: Solve for x
    x = 93,137.14/390.18
  6. Step 6: Final answer
    x = 238.70

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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.