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Finding the Fourth Proportional to 491.47, 678.24 and 304.87

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Solution

The fourth proportional to 491.47, 678.24 and 304.87 is: 420.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.47 : 678.24 = 304.87 : x
  2. Step 2: Convert to fraction form
    491.47/678.24 = 304.87/x
  3. Step 3: Cross multiply
    491.47x = 678.24 × 304.87
  4. Step 4: Simplify right side
    491.47x = 206,774.60
  5. Step 5: Solve for x
    x = 206,774.60/491.47
  6. Step 6: Final answer
    x = 420.72

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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.