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Finding the Fourth Proportional to 665.90, 918.91 and 371.15

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Solution

The fourth proportional to 665.90, 918.91 and 371.15 is: 512.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.90 : 918.91 = 371.15 : x
  2. Step 2: Convert to fraction form
    665.90/918.91 = 371.15/x
  3. Step 3: Cross multiply
    665.90x = 918.91 × 371.15
  4. Step 4: Simplify right side
    665.90x = 341,053.45
  5. Step 5: Solve for x
    x = 341,053.45/665.90
  6. Step 6: Final answer
    x = 512.17

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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.