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Finding the Fourth Proportional to 678.72, 936.29 and 469.10

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Solution

The fourth proportional to 678.72, 936.29 and 469.10 is: 647.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.72 : 936.29 = 469.10 : x
  2. Step 2: Convert to fraction form
    678.72/936.29 = 469.10/x
  3. Step 3: Cross multiply
    678.72x = 936.29 × 469.10
  4. Step 4: Simplify right side
    678.72x = 439,213.64
  5. Step 5: Solve for x
    x = 439,213.64/678.72
  6. Step 6: Final answer
    x = 647.12

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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.