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Finding the Fourth Proportional to 628.70, 943.65 and 385.70

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Solution

The fourth proportional to 628.70, 943.65 and 385.70 is: 578.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.70 : 943.65 = 385.70 : x
  2. Step 2: Convert to fraction form
    628.70/943.65 = 385.70/x
  3. Step 3: Cross multiply
    628.70x = 943.65 × 385.70
  4. Step 4: Simplify right side
    628.70x = 363,961.09
  5. Step 5: Solve for x
    x = 363,961.09/628.70
  6. Step 6: Final answer
    x = 578.92

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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.