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Finding the Fourth Proportional to 645.36, 967.86 and 280.05

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Solution

The fourth proportional to 645.36, 967.86 and 280.05 is: 420.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.36 : 967.86 = 280.05 : x
  2. Step 2: Convert to fraction form
    645.36/967.86 = 280.05/x
  3. Step 3: Cross multiply
    645.36x = 967.86 × 280.05
  4. Step 4: Simplify right side
    645.36x = 271,049.19
  5. Step 5: Solve for x
    x = 271,049.19/645.36
  6. Step 6: Final answer
    x = 420.00

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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.