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Finding the Fourth Proportional to 665.08, 917.89 and 399.67

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Solution

The fourth proportional to 665.08, 917.89 and 399.67 is: 551.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.08 : 917.89 = 399.67 : x
  2. Step 2: Convert to fraction form
    665.08/917.89 = 399.67/x
  3. Step 3: Cross multiply
    665.08x = 917.89 × 399.67
  4. Step 4: Simplify right side
    665.08x = 366,849.80
  5. Step 5: Solve for x
    x = 366,849.80/665.08
  6. Step 6: Final answer
    x = 551.59

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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.