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Finding the Fourth Proportional to 685.37, 1,028.52 and 320.19

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Solution

The fourth proportional to 685.37, 1,028.52 and 320.19 is: 480.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.37 : 1,028.52 = 320.19 : x
  2. Step 2: Convert to fraction form
    685.37/1,028.52 = 320.19/x
  3. Step 3: Cross multiply
    685.37x = 1,028.52 × 320.19
  4. Step 4: Simplify right side
    685.37x = 329,321.82
  5. Step 5: Solve for x
    x = 329,321.82/685.37
  6. Step 6: Final answer
    x = 480.50

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Double scale
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1.5x scale

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.