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Finding the Fourth Proportional to 1,398.34, 2,097.51 and 820

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Solution

The fourth proportional to 1,398.34, 2,097.51 and 820 is: 1,230.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,398.34 : 2,097.51 = 820 : x
  2. Step 2: Convert to fraction form
    1,398.34/2,097.51 = 820/x
  3. Step 3: Cross multiply
    1,398.34x = 2,097.51 × 820
  4. Step 4: Simplify right side
    1,398.34x = 1,719,958.20
  5. Step 5: Solve for x
    x = 1,719,958.20/1,398.34
  6. Step 6: Final answer
    x = 1,230.00

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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.