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Finding the Fourth Proportional to 684.78, 1,027.20 and 636.18

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Solution

The fourth proportional to 684.78, 1,027.20 and 636.18 is: 954.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.78 : 1,027.20 = 636.18 : x
  2. Step 2: Convert to fraction form
    684.78/1,027.20 = 636.18/x
  3. Step 3: Cross multiply
    684.78x = 1,027.20 × 636.18
  4. Step 4: Simplify right side
    684.78x = 653,484.10
  5. Step 5: Solve for x
    x = 653,484.10/684.78
  6. Step 6: Final answer
    x = 954.30

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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.