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Finding the Fourth Proportional to 491.63, 678.51 and 284.63

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Solution

The fourth proportional to 491.63, 678.51 and 284.63 is: 392.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.63 : 678.51 = 284.63 : x
  2. Step 2: Convert to fraction form
    491.63/678.51 = 284.63/x
  3. Step 3: Cross multiply
    491.63x = 678.51 × 284.63
  4. Step 4: Simplify right side
    491.63x = 193,120.91
  5. Step 5: Solve for x
    x = 193,120.91/491.63
  6. Step 6: Final answer
    x = 392.82

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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.