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Finding the Fourth Proportional to 665.62, 918.50 and 400.20

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Solution

The fourth proportional to 665.62, 918.50 and 400.20 is: 552.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.62 : 918.50 = 400.20 : x
  2. Step 2: Convert to fraction form
    665.62/918.50 = 400.20/x
  3. Step 3: Cross multiply
    665.62x = 918.50 × 400.20
  4. Step 4: Simplify right side
    665.62x = 367,583.70
  5. Step 5: Solve for x
    x = 367,583.70/665.62
  6. Step 6: Final answer
    x = 552.24

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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.