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Finding the Fourth Proportional to 685.28, 945.37 and 419.64

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Solution

The fourth proportional to 685.28, 945.37 and 419.64 is: 578.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.28 : 945.37 = 419.64 : x
  2. Step 2: Convert to fraction form
    685.28/945.37 = 419.64/x
  3. Step 3: Cross multiply
    685.28x = 945.37 × 419.64
  4. Step 4: Simplify right side
    685.28x = 396,715.07
  5. Step 5: Solve for x
    x = 396,715.07/685.28
  6. Step 6: Final answer
    x = 578.91

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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.