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Finding the Fourth Proportional to 428.02, 590.74 and 280.40

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Solution

The fourth proportional to 428.02, 590.74 and 280.40 is: 387.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.02 : 590.74 = 280.40 : x
  2. Step 2: Convert to fraction form
    428.02/590.74 = 280.40/x
  3. Step 3: Cross multiply
    428.02x = 590.74 × 280.40
  4. Step 4: Simplify right side
    428.02x = 165,643.50
  5. Step 5: Solve for x
    x = 165,643.50/428.02
  6. Step 6: Final answer
    x = 387.00

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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.