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Finding the Fourth Proportional to 678.59, 1,018.28 and 288.57

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Solution

The fourth proportional to 678.59, 1,018.28 and 288.57 is: 433.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.59 : 1,018.28 = 288.57 : x
  2. Step 2: Convert to fraction form
    678.59/1,018.28 = 288.57/x
  3. Step 3: Cross multiply
    678.59x = 1,018.28 × 288.57
  4. Step 4: Simplify right side
    678.59x = 293,845.06
  5. Step 5: Solve for x
    x = 293,845.06/678.59
  6. Step 6: Final answer
    x = 433.02

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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.