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Finding the Fourth Proportional to 287.55, 429.12 and 256.80

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Solution

The fourth proportional to 287.55, 429.12 and 256.80 is: 383.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.55 : 429.12 = 256.80 : x
  2. Step 2: Convert to fraction form
    287.55/429.12 = 256.80/x
  3. Step 3: Cross multiply
    287.55x = 429.12 × 256.80
  4. Step 4: Simplify right side
    287.55x = 110,198.02
  5. Step 5: Solve for x
    x = 110,198.02/287.55
  6. Step 6: Final answer
    x = 383.23

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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.