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Finding the Fourth Proportional to 379.78, 569.81 and 148.78

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Solution

The fourth proportional to 379.78, 569.81 and 148.78 is: 223.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    379.78 : 569.81 = 148.78 : x
  2. Step 2: Convert to fraction form
    379.78/569.81 = 148.78/x
  3. Step 3: Cross multiply
    379.78x = 569.81 × 148.78
  4. Step 4: Simplify right side
    379.78x = 84,776.33
  5. Step 5: Solve for x
    x = 84,776.33/379.78
  6. Step 6: Final answer
    x = 223.22

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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.