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Finding the Fourth Proportional to 538.80, 743.28 and 317.60

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Solution

The fourth proportional to 538.80, 743.28 and 317.60 is: 438.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.80 : 743.28 = 317.60 : x
  2. Step 2: Convert to fraction form
    538.80/743.28 = 317.60/x
  3. Step 3: Cross multiply
    538.80x = 743.28 × 317.60
  4. Step 4: Simplify right side
    538.80x = 236,065.73
  5. Step 5: Solve for x
    x = 236,065.73/538.80
  6. Step 6: Final answer
    x = 438.13

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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.