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Finding the Fourth Proportional to 304.82, 420.69 and 278.90

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Solution

The fourth proportional to 304.82, 420.69 and 278.90 is: 384.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.82 : 420.69 = 278.90 : x
  2. Step 2: Convert to fraction form
    304.82/420.69 = 278.90/x
  3. Step 3: Cross multiply
    304.82x = 420.69 × 278.90
  4. Step 4: Simplify right side
    304.82x = 117,330.44
  5. Step 5: Solve for x
    x = 117,330.44/304.82
  6. Step 6: Final answer
    x = 384.92

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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.