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Finding the Fourth Proportional to 665.28, 917.82 and 403.20

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Solution

The fourth proportional to 665.28, 917.82 and 403.20 is: 556.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.28 : 917.82 = 403.20 : x
  2. Step 2: Convert to fraction form
    665.28/917.82 = 403.20/x
  3. Step 3: Cross multiply
    665.28x = 917.82 × 403.20
  4. Step 4: Simplify right side
    665.28x = 370,065.02
  5. Step 5: Solve for x
    x = 370,065.02/665.28
  6. Step 6: Final answer
    x = 556.25

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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.