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Finding the Fourth Proportional to 636.61, 878.68 and 388.10

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Solution

The fourth proportional to 636.61, 878.68 and 388.10 is: 535.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.61 : 878.68 = 388.10 : x
  2. Step 2: Convert to fraction form
    636.61/878.68 = 388.10/x
  3. Step 3: Cross multiply
    636.61x = 878.68 × 388.10
  4. Step 4: Simplify right side
    636.61x = 341,012.28
  5. Step 5: Solve for x
    x = 341,012.28/636.61
  6. Step 6: Final answer
    x = 535.67

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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.