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Finding the Fourth Proportional to 890.84, 1,336.02 and 428.30

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Solution

The fourth proportional to 890.84, 1,336.02 and 428.30 is: 642.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.84 : 1,336.02 = 428.30 : x
  2. Step 2: Convert to fraction form
    890.84/1,336.02 = 428.30/x
  3. Step 3: Cross multiply
    890.84x = 1,336.02 × 428.30
  4. Step 4: Simplify right side
    890.84x = 572,217.37
  5. Step 5: Solve for x
    x = 572,217.37/890.84
  6. Step 6: Final answer
    x = 642.33

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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.