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Finding the Fourth Proportional to 678.06, 1,016.26 and 385.80

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Solution

The fourth proportional to 678.06, 1,016.26 and 385.80 is: 578.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.06 : 1,016.26 = 385.80 : x
  2. Step 2: Convert to fraction form
    678.06/1,016.26 = 385.80/x
  3. Step 3: Cross multiply
    678.06x = 1,016.26 × 385.80
  4. Step 4: Simplify right side
    678.06x = 392,076.91
  5. Step 5: Solve for x
    x = 392,076.91/678.06
  6. Step 6: Final answer
    x = 578.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.