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Finding the Fourth Proportional to 662.60, 993.58 and 388.78

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Solution

The fourth proportional to 662.60, 993.58 and 388.78 is: 582.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    662.60 : 993.58 = 388.78 : x
  2. Step 2: Convert to fraction form
    662.60/993.58 = 388.78/x
  3. Step 3: Cross multiply
    662.60x = 993.58 × 388.78
  4. Step 4: Simplify right side
    662.60x = 386,284.03
  5. Step 5: Solve for x
    x = 386,284.03/662.60
  6. Step 6: Final answer
    x = 582.98

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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.