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Finding the Fourth Proportional to 420.02, 579.23 and 280.15

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Solution

The fourth proportional to 420.02, 579.23 and 280.15 is: 386.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.02 : 579.23 = 280.15 : x
  2. Step 2: Convert to fraction form
    420.02/579.23 = 280.15/x
  3. Step 3: Cross multiply
    420.02x = 579.23 × 280.15
  4. Step 4: Simplify right side
    420.02x = 162,271.28
  5. Step 5: Solve for x
    x = 162,271.28/420.02
  6. Step 6: Final answer
    x = 386.34

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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.