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Finding the Fourth Proportional to 664.17, 915.69 and 427.70

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Solution

The fourth proportional to 664.17, 915.69 and 427.70 is: 589.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.17 : 915.69 = 427.70 : x
  2. Step 2: Convert to fraction form
    664.17/915.69 = 427.70/x
  3. Step 3: Cross multiply
    664.17x = 915.69 × 427.70
  4. Step 4: Simplify right side
    664.17x = 391,640.61
  5. Step 5: Solve for x
    x = 391,640.61/664.17
  6. Step 6: Final answer
    x = 589.67

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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.