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Finding the Fourth Proportional to 636.76, 878.75 and 400.78

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Solution

The fourth proportional to 636.76, 878.75 and 400.78 is: 553.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.76 : 878.75 = 400.78 : x
  2. Step 2: Convert to fraction form
    636.76/878.75 = 400.78/x
  3. Step 3: Cross multiply
    636.76x = 878.75 × 400.78
  4. Step 4: Simplify right side
    636.76x = 352,185.43
  5. Step 5: Solve for x
    x = 352,185.43/636.76
  6. Step 6: Final answer
    x = 553.09

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.