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Finding the Fourth Proportional to 665.61, 918.55 and 403.47

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Solution

The fourth proportional to 665.61, 918.55 and 403.47 is: 556.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.61 : 918.55 = 403.47 : x
  2. Step 2: Convert to fraction form
    665.61/918.55 = 403.47/x
  3. Step 3: Cross multiply
    665.61x = 918.55 × 403.47
  4. Step 4: Simplify right side
    665.61x = 370,607.37
  5. Step 5: Solve for x
    x = 370,607.37/665.61
  6. Step 6: Final answer
    x = 556.79

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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.