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Finding the Fourth Proportional to 686.28, 1,028.68 and 626.12

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Solution

The fourth proportional to 686.28, 1,028.68 and 626.12 is: 938.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.28 : 1,028.68 = 626.12 : x
  2. Step 2: Convert to fraction form
    686.28/1,028.68 = 626.12/x
  3. Step 3: Cross multiply
    686.28x = 1,028.68 × 626.12
  4. Step 4: Simplify right side
    686.28x = 644,077.12
  5. Step 5: Solve for x
    x = 644,077.12/686.28
  6. Step 6: Final answer
    x = 938.50

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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.