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Finding the Fourth Proportional to 280.40, 420.60 and 202.10

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Solution

The fourth proportional to 280.40, 420.60 and 202.10 is: 303.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.40 : 420.60 = 202.10 : x
  2. Step 2: Convert to fraction form
    280.40/420.60 = 202.10/x
  3. Step 3: Cross multiply
    280.40x = 420.60 × 202.10
  4. Step 4: Simplify right side
    280.40x = 85,003.26
  5. Step 5: Solve for x
    x = 85,003.26/280.40
  6. Step 6: Final answer
    x = 303.15

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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.