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Finding the Fourth Proportional to 380.81, 570.38 and 258.50

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Solution

The fourth proportional to 380.81, 570.38 and 258.50 is: 387.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.81 : 570.38 = 258.50 : x
  2. Step 2: Convert to fraction form
    380.81/570.38 = 258.50/x
  3. Step 3: Cross multiply
    380.81x = 570.38 × 258.50
  4. Step 4: Simplify right side
    380.81x = 147,439.09
  5. Step 5: Solve for x
    x = 147,439.09/380.81
  6. Step 6: Final answer
    x = 387.18

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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.