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Finding the Fourth Proportional to 379.79, 570.19 and 256.80

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Solution

The fourth proportional to 379.79, 570.19 and 256.80 is: 385.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.79 : 570.19 = 256.80 : x
  2. Step 2: Convert to fraction form
    379.79/570.19 = 256.80/x
  3. Step 3: Cross multiply
    379.79x = 570.19 × 256.80
  4. Step 4: Simplify right side
    379.79x = 146,424.79
  5. Step 5: Solve for x
    x = 146,424.79/379.79
  6. Step 6: Final answer
    x = 385.54

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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.