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Finding the Fourth Proportional to 840.34, 1,259.80 and 320.06

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Solution

The fourth proportional to 840.34, 1,259.80 and 320.06 is: 479.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.34 : 1,259.80 = 320.06 : x
  2. Step 2: Convert to fraction form
    840.34/1,259.80 = 320.06/x
  3. Step 3: Cross multiply
    840.34x = 1,259.80 × 320.06
  4. Step 4: Simplify right side
    840.34x = 403,211.59
  5. Step 5: Solve for x
    x = 403,211.59/840.34
  6. Step 6: Final answer
    x = 479.82

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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.