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Finding the Fourth Proportional to 491.50, 678.35 and 284.62

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Solution

The fourth proportional to 491.50, 678.35 and 284.62 is: 392.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.50 : 678.35 = 284.62 : x
  2. Step 2: Convert to fraction form
    491.50/678.35 = 284.62/x
  3. Step 3: Cross multiply
    491.50x = 678.35 × 284.62
  4. Step 4: Simplify right side
    491.50x = 193,071.98
  5. Step 5: Solve for x
    x = 193,071.98/491.50
  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.