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Finding the Fourth Proportional to 806.45, 1,209.88 and 279.46

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Solution

The fourth proportional to 806.45, 1,209.88 and 279.46 is: 419.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.45 : 1,209.88 = 279.46 : x
  2. Step 2: Convert to fraction form
    806.45/1,209.88 = 279.46/x
  3. Step 3: Cross multiply
    806.45x = 1,209.88 × 279.46
  4. Step 4: Simplify right side
    806.45x = 338,116.67
  5. Step 5: Solve for x
    x = 338,116.67/806.45
  6. Step 6: Final answer
    x = 419.27

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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.