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Finding the Fourth Proportional to 665.10, 917.64 and 403.20

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Solution

The fourth proportional to 665.10, 917.64 and 403.20 is: 556.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.10 : 917.64 = 403.20 : x
  2. Step 2: Convert to fraction form
    665.10/917.64 = 403.20/x
  3. Step 3: Cross multiply
    665.10x = 917.64 × 403.20
  4. Step 4: Simplify right side
    665.10x = 369,992.45
  5. Step 5: Solve for x
    x = 369,992.45/665.10
  6. Step 6: Final answer
    x = 556.30

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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.