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Finding the Fourth Proportional to 428.19, 589.93 and 280.56

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Solution

The fourth proportional to 428.19, 589.93 and 280.56 is: 386.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.19 : 589.93 = 280.56 : x
  2. Step 2: Convert to fraction form
    428.19/589.93 = 280.56/x
  3. Step 3: Cross multiply
    428.19x = 589.93 × 280.56
  4. Step 4: Simplify right side
    428.19x = 165,510.76
  5. Step 5: Solve for x
    x = 165,510.76/428.19
  6. Step 6: Final answer
    x = 386.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.