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Finding the Fourth Proportional to 609.95, 913.30 and 320.78

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Solution

The fourth proportional to 609.95, 913.30 and 320.78 is: 480.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.95 : 913.30 = 320.78 : x
  2. Step 2: Convert to fraction form
    609.95/913.30 = 320.78/x
  3. Step 3: Cross multiply
    609.95x = 913.30 × 320.78
  4. Step 4: Simplify right side
    609.95x = 292,968.37
  5. Step 5: Solve for x
    x = 292,968.37/609.95
  6. Step 6: Final answer
    x = 480.32

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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.