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Finding the Fourth Proportional to 915.29, 1,373.34 and 428.30

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Solution

The fourth proportional to 915.29, 1,373.34 and 428.30 is: 642.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    915.29 : 1,373.34 = 428.30 : x
  2. Step 2: Convert to fraction form
    915.29/1,373.34 = 428.30/x
  3. Step 3: Cross multiply
    915.29x = 1,373.34 × 428.30
  4. Step 4: Simplify right side
    915.29x = 588,201.52
  5. Step 5: Solve for x
    x = 588,201.52/915.29
  6. Step 6: Final answer
    x = 642.64

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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.