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Finding the Fourth Proportional to 3,420, 5,130.72 and 1,368

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Solution

The fourth proportional to 3,420, 5,130.72 and 1,368 is: 2,052.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,420 : 5,130.72 = 1,368 : x
  2. Step 2: Convert to fraction form
    3,420/5,130.72 = 1,368/x
  3. Step 3: Cross multiply
    3,420x = 5,130.72 × 1,368
  4. Step 4: Simplify right side
    3,420x = 7,018,824.96
  5. Step 5: Solve for x
    x = 7,018,824.96/3,420
  6. Step 6: Final answer
    x = 2,052.29

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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.