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Finding the Fourth Proportional to 856, 1,284 and 400

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Solution

The fourth proportional to 856, 1,284 and 400 is: 600

Step by Step Solution

  1. Step 1: Write the proportion equation
    856 : 1,284 = 400 : x
  2. Step 2: Convert to fraction form
    856/1,284 = 400/x
  3. Step 3: Cross multiply
    856x = 1,284 × 400
  4. Step 4: Simplify right side
    856x = 513,600
  5. Step 5: Solve for x
    x = 513,600/856
  6. Step 6: Final answer
    x = 600

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.