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Finding the Fourth Proportional to 890, 1,334.38 and 478.72

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Solution

The fourth proportional to 890, 1,334.38 and 478.72 is: 717.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    890 : 1,334.38 = 478.72 : x
  2. Step 2: Convert to fraction form
    890/1,334.38 = 478.72/x
  3. Step 3: Cross multiply
    890x = 1,334.38 × 478.72
  4. Step 4: Simplify right side
    890x = 638,794.39
  5. Step 5: Solve for x
    x = 638,794.39/890
  6. Step 6: Final answer
    x = 717.75

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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.