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Finding the Fourth Proportional to 280.58, 420.33 and 189.11

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Solution

The fourth proportional to 280.58, 420.33 and 189.11 is: 283.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.58 : 420.33 = 189.11 : x
  2. Step 2: Convert to fraction form
    280.58/420.33 = 189.11/x
  3. Step 3: Cross multiply
    280.58x = 420.33 × 189.11
  4. Step 4: Simplify right side
    280.58x = 79,490.37
  5. Step 5: Solve for x
    x = 79,490.37/280.58
  6. Step 6: Final answer
    x = 283.31

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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.