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Finding the Fourth Proportional to 987.14, 1,480.69 and 256.69

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Solution

The fourth proportional to 987.14, 1,480.69 and 256.69 is: 385.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    987.14 : 1,480.69 = 256.69 : x
  2. Step 2: Convert to fraction form
    987.14/1,480.69 = 256.69/x
  3. Step 3: Cross multiply
    987.14x = 1,480.69 × 256.69
  4. Step 4: Simplify right side
    987.14x = 380,078.32
  5. Step 5: Solve for x
    x = 380,078.32/987.14
  6. Step 6: Final answer
    x = 385.03

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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.