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Finding the Fourth Proportional to 628.60, 942.68 and 217.72

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Solution

The fourth proportional to 628.60, 942.68 and 217.72 is: 326.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.60 : 942.68 = 217.72 : x
  2. Step 2: Convert to fraction form
    628.60/942.68 = 217.72/x
  3. Step 3: Cross multiply
    628.60x = 942.68 × 217.72
  4. Step 4: Simplify right side
    628.60x = 205,240.29
  5. Step 5: Solve for x
    x = 205,240.29/628.60
  6. Step 6: Final answer
    x = 326.50

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Double scale
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Similar ratio
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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.