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Finding the Fourth Proportional to 645.42, 889.34 and 497.60

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Solution

The fourth proportional to 645.42, 889.34 and 497.60 is: 685.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.42 : 889.34 = 497.60 : x
  2. Step 2: Convert to fraction form
    645.42/889.34 = 497.60/x
  3. Step 3: Cross multiply
    645.42x = 889.34 × 497.60
  4. Step 4: Simplify right side
    645.42x = 442,535.58
  5. Step 5: Solve for x
    x = 442,535.58/645.42
  6. Step 6: Final answer
    x = 685.66

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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.