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Finding the Fourth Proportional to 678.40, 1,017.47 and 288.33

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Solution

The fourth proportional to 678.40, 1,017.47 and 288.33 is: 432.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.40 : 1,017.47 = 288.33 : x
  2. Step 2: Convert to fraction form
    678.40/1,017.47 = 288.33/x
  3. Step 3: Cross multiply
    678.40x = 1,017.47 × 288.33
  4. Step 4: Simplify right side
    678.40x = 293,361.54
  5. Step 5: Solve for x
    x = 293,361.54/678.40
  6. Step 6: Final answer
    x = 432.43

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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.