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Finding the Fourth Proportional to 666.80, 920.33 and 442.75

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Solution

The fourth proportional to 666.80, 920.33 and 442.75 is: 611.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.80 : 920.33 = 442.75 : x
  2. Step 2: Convert to fraction form
    666.80/920.33 = 442.75/x
  3. Step 3: Cross multiply
    666.80x = 920.33 × 442.75
  4. Step 4: Simplify right side
    666.80x = 407,471.59
  5. Step 5: Solve for x
    x = 407,471.59/666.80
  6. Step 6: Final answer
    x = 611.08

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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.