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Finding the Fourth Proportional to 644.79, 889.67 and 408.31

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Solution

The fourth proportional to 644.79, 889.67 and 408.31 is: 563.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.79 : 889.67 = 408.31 : x
  2. Step 2: Convert to fraction form
    644.79/889.67 = 408.31/x
  3. Step 3: Cross multiply
    644.79x = 889.67 × 408.31
  4. Step 4: Simplify right side
    644.79x = 363,261.16
  5. Step 5: Solve for x
    x = 363,261.16/644.79
  6. Step 6: Final answer
    x = 563.38

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1.5x scale

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.