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Finding the Fourth Proportional to 456.86, 685.29 and 388.28

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Solution

The fourth proportional to 456.86, 685.29 and 388.28 is: 582.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    456.86 : 685.29 = 388.28 : x
  2. Step 2: Convert to fraction form
    456.86/685.29 = 388.28/x
  3. Step 3: Cross multiply
    456.86x = 685.29 × 388.28
  4. Step 4: Simplify right side
    456.86x = 266,084.40
  5. Step 5: Solve for x
    x = 266,084.40/456.86
  6. Step 6: Final answer
    x = 582.42

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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.