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Finding the Fourth Proportional to 654.11, 981.21 and 288.80

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Solution

The fourth proportional to 654.11, 981.21 and 288.80 is: 433.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.11 : 981.21 = 288.80 : x
  2. Step 2: Convert to fraction form
    654.11/981.21 = 288.80/x
  3. Step 3: Cross multiply
    654.11x = 981.21 × 288.80
  4. Step 4: Simplify right side
    654.11x = 283,368.54
  5. Step 5: Solve for x
    x = 283,368.54/654.11
  6. Step 6: Final answer
    x = 433.22

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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.