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Finding the Fourth Proportional to 1,000, 1,380 and 651.28

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Solution

The fourth proportional to 1,000, 1,380 and 651.28 is: 898.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,000 : 1,380 = 651.28 : x
  2. Step 2: Convert to fraction form
    1,000/1,380 = 651.28/x
  3. Step 3: Cross multiply
    1,000x = 1,380 × 651.28
  4. Step 4: Simplify right side
    1,000x = 898,766.40
  5. Step 5: Solve for x
    x = 898,766.40/1,000
  6. Step 6: Final answer
    x = 898.77

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.