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Finding the Fourth Proportional to 644.88, 889.23 and 479.40

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Solution

The fourth proportional to 644.88, 889.23 and 479.40 is: 661.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.88 : 889.23 = 479.40 : x
  2. Step 2: Convert to fraction form
    644.88/889.23 = 479.40/x
  3. Step 3: Cross multiply
    644.88x = 889.23 × 479.40
  4. Step 4: Simplify right side
    644.88x = 426,296.86
  5. Step 5: Solve for x
    x = 426,296.86/644.88
  6. Step 6: Final answer
    x = 661.05

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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.