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Finding the Fourth Proportional to 319.83, 440.21 and 278.19

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Solution

The fourth proportional to 319.83, 440.21 and 278.19 is: 382.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.83 : 440.21 = 278.19 : x
  2. Step 2: Convert to fraction form
    319.83/440.21 = 278.19/x
  3. Step 3: Cross multiply
    319.83x = 440.21 × 278.19
  4. Step 4: Simplify right side
    319.83x = 122,460.63
  5. Step 5: Solve for x
    x = 122,460.63/319.83
  6. Step 6: Final answer
    x = 382.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.