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Finding the Fourth Proportional to 627.80, 866.75 and 388.55

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Solution

The fourth proportional to 627.80, 866.75 and 388.55 is: 536.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.80 : 866.75 = 388.55 : x
  2. Step 2: Convert to fraction form
    627.80/866.75 = 388.55/x
  3. Step 3: Cross multiply
    627.80x = 866.75 × 388.55
  4. Step 4: Simplify right side
    627.80x = 336,775.94
  5. Step 5: Solve for x
    x = 336,775.94/627.80
  6. Step 6: Final answer
    x = 536.44

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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.