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Finding the Fourth Proportional to 521.70, 781.68 and 228.75

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Solution

The fourth proportional to 521.70, 781.68 and 228.75 is: 342.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.70 : 781.68 = 228.75 : x
  2. Step 2: Convert to fraction form
    521.70/781.68 = 228.75/x
  3. Step 3: Cross multiply
    521.70x = 781.68 × 228.75
  4. Step 4: Simplify right side
    521.70x = 178,809.30
  5. Step 5: Solve for x
    x = 178,809.30/521.70
  6. Step 6: Final answer
    x = 342.74

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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.