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Finding the Fourth Proportional to 636.49, 878.38 and 356.81

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Solution

The fourth proportional to 636.49, 878.38 and 356.81 is: 492.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.49 : 878.38 = 356.81 : x
  2. Step 2: Convert to fraction form
    636.49/878.38 = 356.81/x
  3. Step 3: Cross multiply
    636.49x = 878.38 × 356.81
  4. Step 4: Simplify right side
    636.49x = 313,409.48
  5. Step 5: Solve for x
    x = 313,409.48/636.49
  6. Step 6: Final answer
    x = 492.40

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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.