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Finding the Fourth Proportional to 665.20, 918.02 and 403.28

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Solution

The fourth proportional to 665.20, 918.02 and 403.28 is: 556.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.20 : 918.02 = 403.28 : x
  2. Step 2: Convert to fraction form
    665.20/918.02 = 403.28/x
  3. Step 3: Cross multiply
    665.20x = 918.02 × 403.28
  4. Step 4: Simplify right side
    665.20x = 370,219.11
  5. Step 5: Solve for x
    x = 370,219.11/665.20
  6. Step 6: Final answer
    x = 556.55

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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.