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Finding the Fourth Proportional to 320.40, 438.36 and 319.44

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Solution

The fourth proportional to 320.40, 438.36 and 319.44 is: 437.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.40 : 438.36 = 319.44 : x
  2. Step 2: Convert to fraction form
    320.40/438.36 = 319.44/x
  3. Step 3: Cross multiply
    320.40x = 438.36 × 319.44
  4. Step 4: Simplify right side
    320.40x = 140,029.72
  5. Step 5: Solve for x
    x = 140,029.72/320.40
  6. Step 6: Final answer
    x = 437.05

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.