Home / 840.03-1,259.85-320.09

Finding the Fourth Proportional to 840.03, 1,259.85 and 320.09

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Solution

The fourth proportional to 840.03, 1,259.85 and 320.09 is: 480.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.03 : 1,259.85 = 320.09 : x
  2. Step 2: Convert to fraction form
    840.03/1,259.85 = 320.09/x
  3. Step 3: Cross multiply
    840.03x = 1,259.85 × 320.09
  4. Step 4: Simplify right side
    840.03x = 403,257.49
  5. Step 5: Solve for x
    x = 403,257.49/840.03
  6. Step 6: Final answer
    x = 480.05

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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.