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Finding the Fourth Proportional to 270, 405 and 140

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Solution

The fourth proportional to 270, 405 and 140 is: 210

Step by Step Solution

  1. Step 1: Write the proportion equation
    270 : 405 = 140 : x
  2. Step 2: Convert to fraction form
    270/405 = 140/x
  3. Step 3: Cross multiply
    270x = 405 × 140
  4. Step 4: Simplify right side
    270x = 56,700
  5. Step 5: Solve for x
    x = 56,700/270
  6. Step 6: Final answer
    x = 210

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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.