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Finding the Fourth Proportional to 665.85, 919.21 and 400.44

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Solution

The fourth proportional to 665.85, 919.21 and 400.44 is: 552.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.85 : 919.21 = 400.44 : x
  2. Step 2: Convert to fraction form
    665.85/919.21 = 400.44/x
  3. Step 3: Cross multiply
    665.85x = 919.21 × 400.44
  4. Step 4: Simplify right side
    665.85x = 368,088.45
  5. Step 5: Solve for x
    x = 368,088.45/665.85
  6. Step 6: Final answer
    x = 552.81

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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.