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Finding the Fourth Proportional to 258.30, 356.20 and 228.80

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Solution

The fourth proportional to 258.30, 356.20 and 228.80 is: 315.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.30 : 356.20 = 228.80 : x
  2. Step 2: Convert to fraction form
    258.30/356.20 = 228.80/x
  3. Step 3: Cross multiply
    258.30x = 356.20 × 228.80
  4. Step 4: Simplify right side
    258.30x = 81,498.88
  5. Step 5: Solve for x
    x = 81,498.88/258.30
  6. Step 6: Final answer
    x = 315.52

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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.