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Finding the Fourth Proportional to 678.96, 937.35 and 665.64

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Solution

The fourth proportional to 678.96, 937.35 and 665.64 is: 918.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.96 : 937.35 = 665.64 : x
  2. Step 2: Convert to fraction form
    678.96/937.35 = 665.64/x
  3. Step 3: Cross multiply
    678.96x = 937.35 × 665.64
  4. Step 4: Simplify right side
    678.96x = 623,937.65
  5. Step 5: Solve for x
    x = 623,937.65/678.96
  6. Step 6: Final answer
    x = 918.96

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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.