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Finding the Fourth Proportional to 818.89, 1,228.88 and 386.17

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Solution

The fourth proportional to 818.89, 1,228.88 and 386.17 is: 579.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.89 : 1,228.88 = 386.17 : x
  2. Step 2: Convert to fraction form
    818.89/1,228.88 = 386.17/x
  3. Step 3: Cross multiply
    818.89x = 1,228.88 × 386.17
  4. Step 4: Simplify right side
    818.89x = 474,556.59
  5. Step 5: Solve for x
    x = 474,556.59/818.89
  6. Step 6: Final answer
    x = 579.51

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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.