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Finding the Fourth Proportional to 257.40, 388.17 and 228.60

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Solution

The fourth proportional to 257.40, 388.17 and 228.60 is: 344.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.40 : 388.17 = 228.60 : x
  2. Step 2: Convert to fraction form
    257.40/388.17 = 228.60/x
  3. Step 3: Cross multiply
    257.40x = 388.17 × 228.60
  4. Step 4: Simplify right side
    257.40x = 88,735.66
  5. Step 5: Solve for x
    x = 88,735.66/257.40
  6. Step 6: Final answer
    x = 344.74

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.