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Finding the Fourth Proportional to 685.25, 945.61 and 386.50

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Solution

The fourth proportional to 685.25, 945.61 and 386.50 is: 533.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.25 : 945.61 = 386.50 : x
  2. Step 2: Convert to fraction form
    685.25/945.61 = 386.50/x
  3. Step 3: Cross multiply
    685.25x = 945.61 × 386.50
  4. Step 4: Simplify right side
    685.25x = 365,476.33
  5. Step 5: Solve for x
    x = 365,476.33/685.25
  6. Step 6: Final answer
    x = 533.35

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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.