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Finding the Fourth Proportional to 840.30, 1,259.60 and 320.17

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Solution

The fourth proportional to 840.30, 1,259.60 and 320.17 is: 479.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.30 : 1,259.60 = 320.17 : x
  2. Step 2: Convert to fraction form
    840.30/1,259.60 = 320.17/x
  3. Step 3: Cross multiply
    840.30x = 1,259.60 × 320.17
  4. Step 4: Simplify right side
    840.30x = 403,286.13
  5. Step 5: Solve for x
    x = 403,286.13/840.30
  6. Step 6: Final answer
    x = 479.93

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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.