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Finding the Fourth Proportional to 890.46, 1,338.10 and 479.90

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Solution

The fourth proportional to 890.46, 1,338.10 and 479.90 is: 721.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.46 : 1,338.10 = 479.90 : x
  2. Step 2: Convert to fraction form
    890.46/1,338.10 = 479.90/x
  3. Step 3: Cross multiply
    890.46x = 1,338.10 × 479.90
  4. Step 4: Simplify right side
    890.46x = 642,154.19
  5. Step 5: Solve for x
    x = 642,154.19/890.46
  6. Step 6: Final answer
    x = 721.15

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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.