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Finding the Fourth Proportional to 678.94, 936.78 and 469.30

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Solution

The fourth proportional to 678.94, 936.78 and 469.30 is: 647.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.94 : 936.78 = 469.30 : x
  2. Step 2: Convert to fraction form
    678.94/936.78 = 469.30/x
  3. Step 3: Cross multiply
    678.94x = 936.78 × 469.30
  4. Step 4: Simplify right side
    678.94x = 439,630.85
  5. Step 5: Solve for x
    x = 439,630.85/678.94
  6. Step 6: Final answer
    x = 647.53

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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.