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Finding the Fourth Proportional to 400.78, 600.90 and 340.30

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Solution

The fourth proportional to 400.78, 600.90 and 340.30 is: 510.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.78 : 600.90 = 340.30 : x
  2. Step 2: Convert to fraction form
    400.78/600.90 = 340.30/x
  3. Step 3: Cross multiply
    400.78x = 600.90 × 340.30
  4. Step 4: Simplify right side
    400.78x = 204,486.27
  5. Step 5: Solve for x
    x = 204,486.27/400.78
  6. Step 6: Final answer
    x = 510.22

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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.