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Finding the Fourth Proportional to 257.80, 355.62 and 187.78

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Solution

The fourth proportional to 257.80, 355.62 and 187.78 is: 259.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.80 : 355.62 = 187.78 : x
  2. Step 2: Convert to fraction form
    257.80/355.62 = 187.78/x
  3. Step 3: Cross multiply
    257.80x = 355.62 × 187.78
  4. Step 4: Simplify right side
    257.80x = 66,778.32
  5. Step 5: Solve for x
    x = 66,778.32/257.80
  6. Step 6: Final answer
    x = 259.03

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.