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Finding the Fourth Proportional to 1,380, 2,070 and 354

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Solution

The fourth proportional to 1,380, 2,070 and 354 is: 531

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380 : 2,070 = 354 : x
  2. Step 2: Convert to fraction form
    1,380/2,070 = 354/x
  3. Step 3: Cross multiply
    1,380x = 2,070 × 354
  4. Step 4: Simplify right side
    1,380x = 732,780
  5. Step 5: Solve for x
    x = 732,780/1,380
  6. Step 6: Final answer
    x = 531

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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.