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Finding the Fourth Proportional to 665.49, 918.38 and 370.78

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Solution

The fourth proportional to 665.49, 918.38 and 370.78 is: 511.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.49 : 918.38 = 370.78 : x
  2. Step 2: Convert to fraction form
    665.49/918.38 = 370.78/x
  3. Step 3: Cross multiply
    665.49x = 918.38 × 370.78
  4. Step 4: Simplify right side
    665.49x = 340,516.94
  5. Step 5: Solve for x
    x = 340,516.94/665.49
  6. Step 6: Final answer
    x = 511.68

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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.