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Finding the Fourth Proportional to 490.80, 678.60 and 429.30

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Solution

The fourth proportional to 490.80, 678.60 and 429.30 is: 593.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.80 : 678.60 = 429.30 : x
  2. Step 2: Convert to fraction form
    490.80/678.60 = 429.30/x
  3. Step 3: Cross multiply
    490.80x = 678.60 × 429.30
  4. Step 4: Simplify right side
    490.80x = 291,322.98
  5. Step 5: Solve for x
    x = 291,322.98/490.80
  6. Step 6: Final answer
    x = 593.57

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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.