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Finding the Fourth Proportional to 645.57, 889.38 and 448.74

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Solution

The fourth proportional to 645.57, 889.38 and 448.74 is: 618.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.57 : 889.38 = 448.74 : x
  2. Step 2: Convert to fraction form
    645.57/889.38 = 448.74/x
  3. Step 3: Cross multiply
    645.57x = 889.38 × 448.74
  4. Step 4: Simplify right side
    645.57x = 399,100.38
  5. Step 5: Solve for x
    x = 399,100.38/645.57
  6. Step 6: Final answer
    x = 618.21

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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.