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Finding the Fourth Proportional to 665.90, 918.96 and 371.20

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Solution

The fourth proportional to 665.90, 918.96 and 371.20 is: 512.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.90 : 918.96 = 371.20 : x
  2. Step 2: Convert to fraction form
    665.90/918.96 = 371.20/x
  3. Step 3: Cross multiply
    665.90x = 918.96 × 371.20
  4. Step 4: Simplify right side
    665.90x = 341,117.95
  5. Step 5: Solve for x
    x = 341,117.95/665.90
  6. Step 6: Final answer
    x = 512.27

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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.