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Finding the Fourth Proportional to 667.55, 999.78 and 644.48

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Solution

The fourth proportional to 667.55, 999.78 and 644.48 is: 965.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    667.55 : 999.78 = 644.48 : x
  2. Step 2: Convert to fraction form
    667.55/999.78 = 644.48/x
  3. Step 3: Cross multiply
    667.55x = 999.78 × 644.48
  4. Step 4: Simplify right side
    667.55x = 644,338.21
  5. Step 5: Solve for x
    x = 644,338.21/667.55
  6. Step 6: Final answer
    x = 965.23

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1.5x scale

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.