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Finding the Fourth Proportional to 666.75, 998.75 and 520.35

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Solution

The fourth proportional to 666.75, 998.75 and 520.35 is: 779.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.75 : 998.75 = 520.35 : x
  2. Step 2: Convert to fraction form
    666.75/998.75 = 520.35/x
  3. Step 3: Cross multiply
    666.75x = 998.75 × 520.35
  4. Step 4: Simplify right side
    666.75x = 519,699.56
  5. Step 5: Solve for x
    x = 519,699.56/666.75
  6. Step 6: Final answer
    x = 779.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.