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Finding the Fourth Proportional to 287.15, 428.00 and 279.45

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Solution

The fourth proportional to 287.15, 428.00 and 279.45 is: 416.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.15 : 428.00 = 279.45 : x
  2. Step 2: Convert to fraction form
    287.15/428.00 = 279.45/x
  3. Step 3: Cross multiply
    287.15x = 428.00 × 279.45
  4. Step 4: Simplify right side
    287.15x = 119,603.20
  5. Step 5: Solve for x
    x = 119,603.20/287.15
  6. Step 6: Final answer
    x = 416.53

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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.