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Finding the Fourth Proportional to 328.05, 491.31 and 280.00

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Solution

The fourth proportional to 328.05, 491.31 and 280.00 is: 419.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.05 : 491.31 = 280.00 : x
  2. Step 2: Convert to fraction form
    328.05/491.31 = 280.00/x
  3. Step 3: Cross multiply
    328.05x = 491.31 × 280.00
  4. Step 4: Simplify right side
    328.05x = 137,563.65
  5. Step 5: Solve for x
    x = 137,563.65/328.05
  6. Step 6: Final answer
    x = 419.34

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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.