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Finding the Fourth Proportional to 380.81, 570.75 and 257.15

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Solution

The fourth proportional to 380.81, 570.75 and 257.15 is: 385.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.81 : 570.75 = 257.15 : x
  2. Step 2: Convert to fraction form
    380.81/570.75 = 257.15/x
  3. Step 3: Cross multiply
    380.81x = 570.75 × 257.15
  4. Step 4: Simplify right side
    380.81x = 146,765.51
  5. Step 5: Solve for x
    x = 146,765.51/380.81
  6. Step 6: Final answer
    x = 385.41

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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.