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Finding the Fourth Proportional to 426.90, 589.40 and 279.80

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Solution

The fourth proportional to 426.90, 589.40 and 279.80 is: 386.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.90 : 589.40 = 279.80 : x
  2. Step 2: Convert to fraction form
    426.90/589.40 = 279.80/x
  3. Step 3: Cross multiply
    426.90x = 589.40 × 279.80
  4. Step 4: Simplify right side
    426.90x = 164,909.77
  5. Step 5: Solve for x
    x = 164,909.77/426.90
  6. Step 6: Final answer
    x = 386.30

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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.