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Finding the Fourth Proportional to 390.25, 585.23 and 170.87

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Solution

The fourth proportional to 390.25, 585.23 and 170.87 is: 256.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.25 : 585.23 = 170.87 : x
  2. Step 2: Convert to fraction form
    390.25/585.23 = 170.87/x
  3. Step 3: Cross multiply
    390.25x = 585.23 × 170.87
  4. Step 4: Simplify right side
    390.25x = 99,995.32
  5. Step 5: Solve for x
    x = 99,995.32/390.25
  6. Step 6: Final answer
    x = 256.23

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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.