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Finding the Fourth Proportional to 665.79, 918.81 and 403.66

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Solution

The fourth proportional to 665.79, 918.81 and 403.66 is: 557.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.79 : 918.81 = 403.66 : x
  2. Step 2: Convert to fraction form
    665.79/918.81 = 403.66/x
  3. Step 3: Cross multiply
    665.79x = 918.81 × 403.66
  4. Step 4: Simplify right side
    665.79x = 370,886.84
  5. Step 5: Solve for x
    x = 370,886.84/665.79
  6. Step 6: Final answer
    x = 557.06

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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.