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Finding the Fourth Proportional to 678.17, 935.91 and 412.80

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Solution

The fourth proportional to 678.17, 935.91 and 412.80 is: 569.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.17 : 935.91 = 412.80 : x
  2. Step 2: Convert to fraction form
    678.17/935.91 = 412.80/x
  3. Step 3: Cross multiply
    678.17x = 935.91 × 412.80
  4. Step 4: Simplify right side
    678.17x = 386,343.65
  5. Step 5: Solve for x
    x = 386,343.65/678.17
  6. Step 6: Final answer
    x = 569.69

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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.