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Finding the Fourth Proportional to 287.03, 428.08 and 259.35

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Solution

The fourth proportional to 287.03, 428.08 and 259.35 is: 386.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.03 : 428.08 = 259.35 : x
  2. Step 2: Convert to fraction form
    287.03/428.08 = 259.35/x
  3. Step 3: Cross multiply
    287.03x = 428.08 × 259.35
  4. Step 4: Simplify right side
    287.03x = 111,021.25
  5. Step 5: Solve for x
    x = 111,021.25/287.03
  6. Step 6: Final answer
    x = 386.79

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.