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Finding the Fourth Proportional to 670.09, 1,005.25 and 280.30

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Solution

The fourth proportional to 670.09, 1,005.25 and 280.30 is: 420.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.09 : 1,005.25 = 280.30 : x
  2. Step 2: Convert to fraction form
    670.09/1,005.25 = 280.30/x
  3. Step 3: Cross multiply
    670.09x = 1,005.25 × 280.30
  4. Step 4: Simplify right side
    670.09x = 281,771.58
  5. Step 5: Solve for x
    x = 281,771.58/670.09
  6. Step 6: Final answer
    x = 420.50

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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.