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Finding the Fourth Proportional to 485.28, 667.80 and 419.40

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Solution

The fourth proportional to 485.28, 667.80 and 419.40 is: 577.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.28 : 667.80 = 419.40 : x
  2. Step 2: Convert to fraction form
    485.28/667.80 = 419.40/x
  3. Step 3: Cross multiply
    485.28x = 667.80 × 419.40
  4. Step 4: Simplify right side
    485.28x = 280,075.32
  5. Step 5: Solve for x
    x = 280,075.32/485.28
  6. Step 6: Final answer
    x = 577.14

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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.