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Finding the Fourth Proportional to 685.55, 1,028.05 and 223.20

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Solution

The fourth proportional to 685.55, 1,028.05 and 223.20 is: 334.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.55 : 1,028.05 = 223.20 : x
  2. Step 2: Convert to fraction form
    685.55/1,028.05 = 223.20/x
  3. Step 3: Cross multiply
    685.55x = 1,028.05 × 223.20
  4. Step 4: Simplify right side
    685.55x = 229,460.20
  5. Step 5: Solve for x
    x = 229,460.20/685.55
  6. Step 6: Final answer
    x = 334.71

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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.